Yes, we're back in the Dreadlands, and I've been playing Jojo's Bizarre Adventure too much. This was inspired by the series' Stand gimmick.
Spirit Fighter
While many summoners send their eidolon to do their fighting for them, there are some that defy this notion, and battle side-by-side with their partner. Spirit fighters have the following class features.
-Weapon and Armor proficiencies
Spirit fighters are proficient with all simple and martial weapons They keep the normal summoner armor proficiencies. This replaces the summon monster spell-like ability.
-Spirit Companion (Su)
The eidolon of a spirit fighter is unique among its kind. The eidolon cannot move more than 20 feet from its summoner. However, it can occupy the same space as its summoner without penalty. In addition, its semi-incorporeal nature grants the eidolon DR 2/–.
The eidolon also recovers far more quickly than others of its kind. If banished, it can be summoned again a number of hours later equal to 21 - the spirit fighter’s caster level (minimum 1).
This otherwise functions like and replaces the standard eidolon.
-Life Bond (Su)
The spirit fighter is bonded even more closely with his eidolon than other summoners, for good or ill. Whenever the eidolon takes damage, the spirit fighter receives half of that damage (rounded up, no save). However, when the eidolon and spirit fighter are within 5 feet of each other, the spirit fighter and eidolon gain a deflection bonus to AC equal to the spirit fighter’s caster level. This replaces life link.
Whooo boy. Deflection bonus equal to caster level? That's a really, really high bonus, especially for a class that can wear armor and has a CL = to its level. And Deflection is the best type of defensive bonus in the game, as it applies at all times, against both touch and flat-footed AC.
It's already really easy to get an eidolon's defensive stats up there really high, and deflection is one of the few bonus types that summoner spells can't grant. Taking damage from hits to your eidolon isn't a problem when your eidolon never gets hit at all.
I think there's room for a fighting-focused summoner archetype - I'm planning on playing a barbarian/summoner melee guy when I cash in my PFS GM credits, and would love to see something.
If I were going to build one, I'd try and focus it around either teamwork feats or the summoner picking up evolutions, and trade out the Summon Monster SLAs as you did. I'd also give the summoner a closer bond with the eidolon by allowing either one to take damage for the other, allowing the Life Link ability to work both ways.
Keep in mind, I was thinking of Jojo's Bizarre Adventure. With most of the Stands, if the Stand takes damage, so too does its master. That's how the villain of Part 3 is killed; His Stand is shattered, and he collapses into a bloody pile of giblets.
I'll keep the deflection thing in mind, perhaps half of his CL?
I've done something absolutely crazy with this archetype: I got rid of the ability to cast spells.
Spirit Fighter (summoner)
While many summoners send their eidolon to do their fighting for them, there are some that defy this notion, and battle side-by-side with their partner. Spirit fighters have the following class features.
-Weapon and Armor proficiencies
Spirit fighters are proficient with all simple and martial weapons They keep the normal summoner armor proficiencies. This replaces the summon monster spell-like ability.
-Strength-dependent
All of the summoner's Charisma-based class features (other than spells and summon monster, which the spirit fighter lacks) are based on Strength instead.
-Spirit Companion (Su)
The eidolon of a spirit fighter is unique among its kind. The eidolon cannot move more than 20 feet from its summoner. However, it can occupy the same space as its summoner without penalty. In addition, its semi-incorporeal nature grants the eidolon DR 2/–.
The eidolon also recovers far more quickly than others of its kind. If banished, it can be summoned again a number of hours later equal to 21 - the spirit fighter’s caster level (minimum 1).
This otherwise functions like and replaces the standard eidolon.
-Life Bond (Su)
The spirit fighter is bonded even more closely with his eidolon than other summoners, for good or ill. Whenever the eidolon takes damage, the spirit fighter receives half of that damage (rounded up, no save). However, when the eidolon and spirit fighter are within 5 feet of each other, the spirit fighter and eidolon gain a deflection bonus to AC equal to half of the spirit fighter’s caster level (minimum +1). This replaces life link.
-Spirit Power (Su)
At 4th level, the eidolon specializes in a certain ability. Once this choice is made, it cannot be changed. This replaces the summoner's ability to cast spells.
Blazing Fists: The eidolon can perform a flurry of blows, as a monk equal to its master's summoner level -2.
Energy Barrage: The eidolon can use one of the following as a spell-like ability: acid splash, ray of frost, magic missile, burning hands. The eidolon may use a full-attack action to barrage the enemy. Each cast spell counts as one attack (with the exception of burning hands and magic missile, which are used once for every three attacks). The spell choice is made at 4th level and cannot be changed. The Energy Barrage can be used a number of times per day equal to its master's Strength modifier.
Home Smite: The eidolon channels the power of its home plane. Depending on the eidolon's alignment, it may smite evil, good, law, or chaos a number of times per day equal to 3 + its master's Strength modifier. Neutral eidolons choose one of these, and it cannot be changed.
I really like the idea in general.
I, too, worry about the deflection bonus. Eidolons really can get high ACs already. More thematically, I think using the higher of the summoner's or the eidolon's might work better. Or a 20% miss chance as one provides interference for the other.
Either drop the semi-incorporeal nature or embrace it fully. As is it makes no sense even in a magic fueled fantasy game. It should either be there or not.
As for trading out spells . . . what you offer doesn't even begin to make up for loss of spells like haste, black tentacles, and others. Not even if you offered all of them.
As a final note: consider offering the summoner something. Without the eidolon he currently has neither SLAs nor spells. Even the rogue will look down and pity him.
The thing is, the summoner doesn't have anything else that I could fairly replace, and I don't want to just hand him something better than his normal features. I believe in archetypes being sidegrades, not upgrades.
(geez, first the Spirit Fighter was OP, now he's pathetically weak)