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Basics: For those who don't have the book, the basics of the Summon Monster spell: It's a 1-6 variable level Mystic and Technomancer spell, still 1 round casting time, you either get one creature of your highest level list, or three of a lower level list. The Technomancer and Mystic versions differ in only one way: only Technomancers can summon Robots, and only Mystics can summon First World Creatures.
Choosing Summons: Instead of everyone picking from a fixed list (expandable via feats and religious dedication and items in Pathfinder), you pick four creatures for every level that you can summon at that level. If you choose to use to learn this spell twice at the highest level you can cast it, you can pick eight creatures per level for maximum flexibility. I wouldn't, though.
What You Can Get: Usually these creature options are outsiders based on the Alien Archive Elemental base stats and modified by a graft. So if you want to summon a devil, you don't get a specific devil like in Pathfinder, you get the Elemental stats for that level and then modify it with the devil graft. There are a few exceptions where you just summon a creature of more or less the appropriate CR from the Alien Archive modified by a simple template (the Starfinder Equivalent of celestial/infernal animals), but these are fewer than the outsider options.
Monster CR: The CR range of the base elemental at various Summon Monster levels is as below. Remember, you can pick three of a lower level.
Level 1: CR 1/3
Level 2: CR 1
Level 3: CR 3
Level 4: CR 5
Level 5: CR 7
Level 6: CR 11
Note that there is a CR 9 ("Greater Elemental") version that is skipped over between Level 5 and Level 6 list. My guess is this is an incentive to keep a single CR 11 creature rather than always go for three of the lower level.
Alignment: For non-Elemental outsiders, there are alignment restrictions preventing some summoners from choosing some options. You can't have an opposing alignment to a non-neutral component of a summon (no LE devils if you are either chaotic OR good), and Aeons can't be summoned unless you have some neutral component (no CE or LG need apply). Otherwise you're fine.
Base Stats: The noteworthy base stats of the elemental, before grafts, are: 20' speed, a slam attack dealing bludgeoning damage, darkvision, and saves that are Fort high, Reflex medium, and Will low. At higher levels they get reach and DR/-. The only skills they get are Athletics and Acrobatics.
The grafts then modify this by changing the DR (often introducing a way to bypass with aligned or special material attacks), adding movement modes or speeds (most get at least 30' base, many get a slow fly speed), adding senses, adding attack modes (or changing damage type), adding skills, adding languages, and adding resistances/immunities/vulnerabilities.
Note that in addition to a weak Will save, only one graft (Shadow Creature) has any SR, and that's weak (CR+5).
Finding the Best Grafts: So what are the "best" grafts that provide interesting abilities? Some, like Angels and Demons, get a variety of abilities (resistances/immunities, fly speed, some skills) but none of them standout. They can fight in general, but they don't specialize strongly or bring any "wow" factors. Below I want to focus on those that do something exceptional that you might want to seek out and focus on as a summoning strategy. You can also pick up a generic one for flexibility and average situations or flavor, but of your four picks per level I think two speciality outsiders are wise before you pick a generic option or grab a rare non-outsider monster option.
Ranged attacks: Archon (fire damage 60' increment), Azata (piercing damage 120'), Daemon (piercing damage 30'), Inevitable (electricity damage 50' increment), Robot (sonic damage 40' increment). [Energy damage is in line with melee but without strength bonus. Piercing damage is a bit higher. The Robot and Azata pay for their special damage type/range advantages with a lower melee attack bonus.]
Skills: Aeon (Culture, Engineering, Life Science, Mysticism, Physical Science), Robot (Computers), Inevitable (Engineering), Shadow Creature (Stealth and can HIPS out of bright light)
Senses: Devil (see in darkness), First World Beast (blindsense (scent)), Protean (blindsense (hearing))
Melee: Agathian (multiattack at higher CR only), First World Beast (grab), Protean (grab), Shadow creature (cold damage, targets EAC)
Movement: Air Elemental (100' perfect fly), Earth Elemental (20' burrow), Water Elemental (90' swim), Protean (60' perfect fly), Angel (30/60' perfect fly), Archon (30/60' perfect fly),
Resistances/Immunities: These are all over the place. Lots of things are immune to a particular energy, most things are resistant to a few energy or attack types, daemons are immune to death effects, Inevitables get regeneration, Robots get construct/unliving immunities, and most things (but not Robots, Elementals, Inevitables, and Aeons) pick up a vulnerability (usually aligned damage) that can bypass their DR.
Notable Mentions:I think the standouts are the Inevitable (ranged, durable, Engineering skill), Aeon (knowledge/disable skill monkey and telepath), Air Elemental (air superiority), Archon (floating full attacking laser platform), Robot (hacking, hard to resist ranged damage, lots of immunities), Agathion (highest DPR at spell level 5 and 6).
Sad Trombone: I can't see any practical reason to prefer the First World Creature over a Protean in combat, and the skills aren't really usable given the duration. The Devil isn't quite bad, but other than laser immunity (admittedly sometimes amazing!) and see in darkness it has nothing really going for it; the Demon is similarly hard up with only average flight and some full spectrum resistances. The Angel is straight outclassed by the Archon offensively.
Others' thoughts?
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Looking at it, I'm not sure I disagree all that much, though I will note one factor you seem to be ignoring is Perception.
First World Beasts, Inevitables, and Shadow Creatures are the only ones to get it, and it's potentially very relevant in many encounters. Based on that and their other tricks (two elemental immunities, two other resistances, HiPS, Stealth, their attack being vs. EAC but at the same damage) I'd add Shadow Creatures to your standouts list.
Probably Azata, too. They don't fly, but their other defensive stuff is pretty solid, and their ranged offense is actually better than the Archon's (including double the range) and that's not nothing.
I'd argue Devil's advantages, which you note, make it an alright choice (though not a standout) and that the problem with Angel is less Archon specifically being better and more Agathion being better in melee and the other two Good options being better at range. It's sorta betwixt and between more than anything really wrong with it. But yeah, First World Creature is just eclipsed by Protean, and Demon and Angel are overshadowed by other options.
Looking at it, I'm not sure I disagree all that much, though I will note one factor you seem to be ignoring is Perception.
First World Beasts, Inevitables, and Shadow Creatures are the only ones to get it, and it's potentially very relevant in many encounters. Based on that and their other tricks (two elemental immunities, two other resistances, HiPS, Stealth, their attack being vs. EAC but at the same damage) I'd add Shadow Creatures to your standouts list.
Skill bonuses are not very high at each level, and you’re still up against a full round casting time and short duration. I tried to think of a reliable and foreseeable use for Perception on a Summon given those limitations and all I came up with was a very bad chance of pinpointing an invisible foe instead of no chance. Summoners have better methods of doing that, including picking a Blindsense or Tremorsense (sorry, Earth Elemental, forgot you) summon over a Perception one.
But Inevitable and Shadow Creature are already nice, so it’s a fine bonus.
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Looking at it, I'm not sure I disagree all that much, though I will note one factor you seem to be ignoring is Perception.
Frankly, by RAW, I think the skill "Perception" is meaningless in relation to determining which is better. If you follow the rules on "building" a summoned creature, it appears the creature has the same Perception bonus regardless of whether it has the Perception skill.
For example, a Level 1 First World Beast.
Step one, you start with the Tiny Elemental stat block which does NOT have the Perception skill, but gives a Perception bonus of +3 (up in the Senses section).
Step two, you apply the First World Beast Graft. In doing so, you add the Perception skill to the list of skills possessed. Pursuant to the Graft rules, any added skill gets the same total skill bonus as the base stat block's existing skills, which is +3.
So, you get the same Perception bonus (+3) regardless of whether the creature has or does not have the Perception skill.
I spot checked the other levels and it seems to hold true at higher levels.
Whether this makes any sense or was or was not intended by the designers, I don't know. I'm just following the mechanics presented in the Alien Archives book.
As an aside, although the Monster and NPC creation rules are NOT referenced for summoned creatures, I do note that Perception is always a "good" skill for Monsters/NPCs, which for a CR 1/3 creature (like the level 1 summoned creatures) would be a +3 bonus (which matches the template's +3 bonus for Perception). I further note that a Monster/NPC can have "Master Skills" which for a CR 1/3 gives a +7 bonus. I don't think it unreasonable for a GM to decide that a summoned creature that actually has Perception as a skill treats it as a master skill and gets Perception +7 rather than the normal Perception +3 (for a level 1 summons). But I would consider this a house rule.
It's worth pointing out that summons are stronger in Starfinder than in Pathfinder. At least when it comes to attack bonuses and damage.
At 1st level, the spell summons a creature roughly as strong as a creature summoned by summon monster II.
At 6th level, the spell summons a creature roughly as strong as a creature summoned by summon monster VIII.
So while creatures don't have as many powerful special abilities, they're better attackers.
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I would note that the selection of "best" grafts for Level 1 for COMBAT is significantly different than the selection at higher levels. At level 1, the creatures are TINY, which means they must enter an enemy's square to attack them and do NOT flank. This is not a problem at level 2+ as the creatures become small or bigger and can threaten/attack adjacent squares. So, for combat, grafts that provide ranged attacks may be a bit better choice at level 1 since they don't have to enter the enemy's square. Also, the Skittermander Whelp gets 5' reach with it's bite attack, so despite it's size, does not have to enter a defender's square to attack it in melee.
Note, if I understand the AOO rules correctly, one change from Pathfinder is that a Tiny creature entering another creature's square does not per se trigger an AOO. It appears to me that if the Tiny creature takes a Guarded Step into the other creature's square, there is no AOO.
Let's compare Summon Monster VI to Battle Junkbot at CL 16 when they are both available. Note that the Junkbot HP, attack, and AC scale as CL increases.
Reach: 15' for the summon, 5' for the Junkbot.
Attack bonus: +24 for the summon, +21 for the Junkbot
Melee damage: 4d6+19 (avg 33) for summon, 6d8+6 (avg 33) for the Junkbot
Ranged damage: up to 3d8+11 (F/E/So) (avg 20.5) or 3d10+11P (avg 27.5) for the summon, 6d6F (avg 21) for the Junkbot. The summon can get a better range increment.
AC: 24/26 for the summon, 31/31 for the Junkbot
HP: 145 for the summon, 42(!!!) for the Junkbot (assuming 4 racial HP on the Technomancer)
Saves: Fort +15, Reflex +13, Will +10 for the summon, as the Technomancer for the Junkbot
DR/Hardness: 10/- for the summon (may have vulnerability for some grafts), Hardness 15 for the Junkbot
Resistances/Hardness: A variety of energy resistances of 11 available depending on graft for the summon, Hardness 15 for the Junkbot
Immunities: Highly variable depending on graft for the summon, construct/unliving immunities for the Junkbot.
Movement: Depends on the graft, but generally 30' and up to 60'/100' flight for the summon, 30' and 15' flight for the Junkbot.
Spell range: Medium for the summon, touch (requiring it to move to attack) on the Junkbot
Special: Grab, multiattack, and senses are available to summon grafts, the Junkbot gets combat maneuver feats for bull rush, grapple, and trip.
Overall, it's really hard to make the case for the Junkbot anymore unless you're always fighting in 5' corridors. The only significant advantages it has are a really good AC and slightly better damage reduction, but terrible HP, bad range, material components, and a lack of SM's flexibility kill it for me.
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Let's compare Summon Monster VI to Battle Junkbot at CL 16 when they are both available. Note that the Junkbot HP, attack, and AC scale as CL increases.
...
Overall, it's really hard to make the case for the Junkbot anymore unless you're always fighting in 5' corridors. The only significant advantages it has are a really good AC and slightly better damage reduction, but terrible HP, bad range, material components, and a lack of SM's flexibility kill it for me.
Ah, but the Junkbot can be used in places where you might be prevented from summoning creatures, and is not subject to spells that affect summoned creatures (like Dismissal). It's a transmutation spell that actually creates a robot from stuff lying around. It also has special rules regarding communication and awareness between the Junkbot and the master, which could be useful in some situations (particularly where the master is sending the Junkbot into battle, but is not himself going to be present).
I don't see them in the current spell list, but I expect Paizo to add to the spell list, so there may eventually be spells that protect against summoned creatures (like Pathfinder's Magic Circle spells). These may affect the Summoned creature, but not the Junkbot.
In any case, I wouldn't dismiss the Junkbot as a spell you would never take.
That said, if I had only one spell known to choose, and it was between Summon Creature VI and Junkbot, I probably would go with the Summon Creature VI as its generally more useful (whereas Junkbot can be very useful in specific situations).
Looking at it, I'm not sure I disagree all that much, though I will note one factor you seem to be ignoring is Perception.Frankly, by RAW, I think the skill "Perception" is meaningless in relation to determining which is better. If you follow the rules on "building" a summoned creature, it appears the creature has the same Perception bonus regardless of whether it has the Perception skill.
This is a good catch. And good suggestion on Master skills.
I will say that the Summon's ability to use Perception may also have some out-of-combat utility, especially at higher levels. At that point, the Summon will ideally be cast before combat, and/or linger a bit after combat. This means that they can be used to scout, to look for traps, and to search the battlefield. Also if you enter a new combat, the Perception may come up in a surprise round, depending on how your GM adjudicates it.
If your party doesn't have a Mystic or Operative, a Summon probably has a better Perception than anyone in your party (even without allowing for "Master" skills). And at lower levels, their Perception is about even with a 10-WIS Operative.
I also think the Earth Elemental deserves a space in the "melee" category. It's true that its +1 bonus will likely benefit it less than in PF, but since maximizing DPR will very often be the top priority in summon choice, and no other graft gives any kind of bonus to melee damage or attacks, they probably deserve recognition.
As for the Agathion's multiattack, the high level elementals also have multiattack, though its benefit is unclear. My guess is the intent is for them to make 3 slam attacks.
As for the Agathion's multiattack, the high level elementals also have multiattack, though its benefit is unclear. My guess is the intent is for them to make 3 slam attacks.
I think that’s just an error, the melee damage on the CR 11 is wrong, I think they also messed up by replacing the meleeline with multi attack.
Away from the book, but you mean the base stats (which apply to all outsiders adding a graft), not the specific elemental grafts, right?
I was hoping for a summon monster spell closer to the Pathfinder version, with summoning distinct monsters. The loss of summons with unique abilities also kinda hurts and limits what summon monster can be used for.
That said the monsters do seem to scale better in combat stats, and that should keep them useful at higher levels for combat. The idea of summoning an elemental and applying a graft does make it clear that you're using planar essence to mimic a creature rather than pulling one from it's home plane, but the debates around that occurred because you could do things like summon a succubus for their profane gift.
All told I'm ok with this version, it's just not what i was expecting.
Unique abilities seem to be the domain of the few alien archive monsters that earn a spot on a list. The ksaarik imitation ability gives flexible access to lots of stolen abilities after they hit, and those huge eel things (?) have a paralysis ability that seems dangerous if you summon a flesh wall of three. I also noticed that a monster, but no outsider, has See Invisibility.
It letting SM be a spammable healing or darkness spell is actually good.
I think that’s just an error, the melee damage on the CR 11 is wrong, I think they also messed up by replacing the meleeline with multi attack.
Away from the book, but you mean the base stats (which apply to all outsiders adding a graft), not the specific elemental grafts, right?
Correct.
There's definitely AN error in the multiattack line; the question is whether the error is replacing Melee with Multiattack or in failing to spell out the multiattack. Though I don't expect to be playing any Level 16 characters any time soon, so I'm not too worried about it at the moment.
One advantage of this spell relative to PF that I haven't seen anyone call out: it's medium range. Which is probably there since the changes to Concentration mean that casting this anywhere near the front lines is a bad idea. But the change to medium definitely favors melee summons.
Overall, melee seems to be the better option in most combat situations. The Air elemental's movement is greater than the range increment of nearly all of the ranged attackers. And unlike PF where the Air Elemental's slams were pathetic (and flying summons in general were weak), here it hits as hard as anything else. Plus it still has Whirlwind.
And melee summons with reach will be great for harassing casters and ranged attackers. Especially if it's a Protean who risks grabbing them if they provoke an AOO by trying to move away.
I think the biggest advantage of the ranged summons is not range itself but the variety of damage types (and by extension, more attacks that target EAC).
The thing I like is that it will be easy to add creatures to the summon creature lists. Whenever a new graft is printed in a supplement, all that is needed is some text mentioning how it can be applied to creatures summoned with Summon Creature spells, as well as any other prerequisites it might have.
I think that’s just an error, the melee damage on the CR 11 is wrong, I think they also messed up by replacing the meleeline with multi attack.
Away from the book, but you mean the base stats (which apply to all outsiders adding a graft), not the specific elemental grafts, right?
Correct.
There's definitely AN error in the multiattack line; the question is whether the error is replacing Melee with Multiattack or in failing to spell out the multiattack.
There are at least three errors.
1. The damage is wrong.
2. The “melee” line is missing; this has to be there even if it also has a multiattack option.
3. It says multiattack but doesn’t list damage and attack bonuses for multiple attacks.
Since the Agathion gets MA as a special ability the most parsimonious explanation is that the basic CR 11 stat block should read melee instead of multiattack and the damage fixed.
A couple of random points:
1. The base Tiny elemental doesn't have the space/reach entry of a standard Tiny creature. Presumably a mistake.
2. The base Elder elemental has the HP of a CR 9 combatant, rather than a CR 11 combatant, possibly copied and not changed from the base Greater elemental. It should probably have 180 hp.
3. According to the stat block creation rules, Perception never goes on the skill line; it always only shows up at the top of the block.
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Yeah, I wanted to get to a discussion of the unique monster summons. They are:
SM1: Skittermander welp
SM2: Security robot (observer class)
SM3: Crest-eater; Haan; Ksarik
SM4: Mountain Eel; Orocoran
SM5: Surnoch
SM6: NONE
For each I'll compare raw combat ability to the base outsider template, then discuss special abilities.
SM1
Baseline Outsider attack: +5 (1d6+3)
Skittermander whelp: +2 (1d4-2P plus attach)
Verdict: Terrible, other than 5' reach there's nothing here you want. Just go ranged on outsiders at this level.
SM2
Baseline Outsider attack: +9 (1d6+5)
Security robot (observer class): melee +6 (1d6+3B), ranged +9 (1d4+1 nonlethal) or +9 entangle grenade with DC 10; AC is a couple of points higher
Verdict: This is the only nonlethal SM option and entangle is theoretically nice, but the damage and DC are too low to be reliable. I say skip.
SM3
Baseline Outsider attack: +12 (1d6+7)
Crest-Eater: melee +13 (1d6+7 P plus 1 Con), 60' land speed(!), 10' reach. It also has notably higher AC and more HP than an Outsider.
Verdict: BUY! BUY! BUY!
Haan: melee +10 (1d4+5 S), balloon lifting attack, 3d6F 30' cone attack, 10' reach
Verdict: The balloon attack is fantastic against low reflex enemies who can't fly and don't have ranged attacks. That's...not many, unfortunately. I think this works best as a triple summon at SM4, all three can set up overlapping cones to deliver 9d6F per round, the same as a single Explosive Blast spell, albeit with a much worse DC. The space and reach also work for blocking and setting up an AoO zone. This is an ok pick but you won't regret letting it go, either.
Ksaarik: melee +12 (1d6+9 B plus ingested adaptation), ranged +9 (1d4+4 A) or +9 (1d6+4 P plus carrion spores)
Verdict: The adaptation is theoretically interesting in its ability to poach a key ability from something you're fighting, but I don't think in practice setting strength against strength helps that much. An inaccurate, low damage acid attack doesn't save this. Pass.
SM4
Baseline Outsider attack: +15 (1d6+10 B)
Mountain Eel: melee +16 (1d8+11 P), 25 more HP, slight AC bonus, DC 14 or 1rd paralyze effect on everything within 60', 40' movement and trample with 15' space
Verdict: I love these big, stupid things. 10' reach is no longer an advantage over outsiders at this level, and the Mountain Eel has 15' space so it's not very usable in tight quarters. But if you can drop one next to or in the middle of a bunch of enemies that paralyze zone is like whoa as you trample through them. Someone is going to fail the save, taking them out of the fight for a round and setting up a potential CDG. Don't worry about the AoOs you soak up, just let it wreak havoc.
Orocoran: melee +13 (1d8+6 P; critical bleed 1d6), ranged +16 (1d10+6 A plus hallucinate), 23 extra HP, See Invsibility
Verdict: See Invisibility, a decent ranged attack bonus with a hard to resist damage and potential Confusion effect, this can easily push away one of your standard outsider ranged grafts at this level.
SM5
Baseline Outsider attack: +18 (2d6+12 B)
Surnoch: melee +21 (2d10+12 P), ranged +18 (3d6+9 A) (line 60'), +3 AC, +40 HP, higher saves, but 10' reach/space vs. 15' on the outsider, bonus damage to grappled creatures (3d6+9 A/P) but no special grappling abilities, 30' burrow, no DR, no breath ability so vacuum capable
Verdict: Smaller (which sometimes can be a benefit) but much tougher than an outsider, the burrow can allow it to conduct interesting tactical movement in certain planetary (and asteroid!) environments, and the acid line attack is solid. This is an interesting and defensible pick and adds some fun variety; if they errata it to give it Grab to go with the otherwise not very useable Corrosive Spines, this becomes amazing.
Thanks, this is helpful.
I hadn't thought about the fact that Level 1 base summons lack 5 ft. reach. I guess that's the only reason Skittermander whelp exists as an option (besides fun factor). But note that this means it can provide a flank, unlike the other options. So yes, it's generally terrible, but at high levels it will be the only 1st level summon that can do anything in a fight (besides Aid Another). The Whelp can both flank AND Aid Another.
Hopefully the enemy won't have AOEs, in which case it will either provide some bonuses or at least eat an attack. Summon it before the fight though, not during.
Actually, I guess Aid Another is no longer a melee combat option, and I forgot about Harrying Fire and Covering Fire.
Using 1st level ranged summons to do these things might not be a bad idea at higher levels -- they'll succeed half the time. And it's probably better than trying to position your Skittermander to flank, which will probably work out less than half the time.
So TLDR, Xenocrat is right, Skittermander whelp is probably useless, move along.
A Steward and three pirates walk into a jungle. The Steward casts summon monster, but nothing appears to happen. The pirates laugh. The Steward laughs. The sneaky whelps attached to the pirates' backs laugh...
>:D
A Steward and three pirates walk into a jungle. The Steward casts summon monster, but nothing appears to happen. The pirates laugh. The Steward laughs. The sneaky whelps attached to the pirates' backs laugh...
>:D
Yep, that's that "fun factor" I was referring to! They are cool little creatures.
Reviewing this thread in anticipation of Alien Archive 2 adding some new summonable monsters, and it occurs to me that the SC5 Surnoch option should work as a permanent tunneler for a mystic/technomancer who wants to build an asteroid base or dig underneath a a target facility. If you read the monster description, it's burrow 30' works through stone, and leaves neatly sculpted tunnels behind it. Must faster (and lower level) than repeated Disintegrate castings.
I was hoping for a summon monster spell closer to the Pathfinder version, with summoning distinct monsters. The loss of summons with unique abilities also kinda hurts and limits what summon monster can be used for.
That said the monsters do seem to scale better in combat stats, and that should keep them useful at higher levels for combat. The idea of summoning an elemental and applying a graft does make it clear that you're using planar essence to mimic a creature rather than pulling one from it's home plane, but the debates around that occurred because you could do things like summon a succubus for their profane gift.
All told I'm ok with this version, it's just not what i was expecting.
This version is a lot more open in what you can summon however - if they had made it summon distinct creatures with their own stat blocks, they would have had to either add roughly 100 more creature entries to the alien archive, or severely limit what the spell can summon. At least this way you can have a character that always is able to summon the type of creature that fits their theme, instead of being like "Im level 1 so there are no devils for my asmodeus worshipping mystic to summon"
If they are clever they will probably add a table in future alien archives adding any specific appropriate creatures from those books to the list though.
I'm extremely befuddled that Alien Archive 2 didn't add more Summon Creature options. It makes zero sense for non-outsiders to even be options if it's just the arbitrary few from the original book.
There probably should have been a page or even half page with additional summon grafts.
That said, with the summon grafts we do have, it's very easy to create additional similar grafts to fit just about any subtype. Is it worth printing, or worth printing a rule to make your own?
There probably should have been a page or even half page with additional summon grafts.
That said, with the summon grafts we do have, it's very easy to create additional similar grafts to fit just about any subtype. Is it worth printing, or worth printing a rule to make your own?
I didn't expect more outsider grafts, those appear to be fully covered, I expected more aliens. Why can Summon Monster create a Mountain Eel, a Haan, or an Orocoran, but not any of the aliens from this book? It would be fine if Summon Monster only did outsiders with grafts, but if it can do some aliens, it makes zero sense for it to be arbitrarily limited to those few from the original book. Surely magicians throughout the galaxy who have never met any of those species can't summon them, but can instead summon creatures they are familiar with.
True, I imagine they don't want to recreate the issues pathfinder had with summoning certain monsters being the obvious choice. The lillend azatas, the t-rex, etc. I don't know how effective they've been, the mountain eel already seems like a top choice.
I suppose they could have carefully considered 4-6 monsters from the book and thrown a note in their entry 'this creature can be summoned by summon monster X'.