CR 13 T-Rex

[My Self]

Regular T-rexes are CR 9. In 4 levels worth of CR, how deadly can you make a T-rex? I was thinking UMonk, Feral Combat Training, and maybe some style feats such as Dragon Style/Dragon Ferocity or Panther Style, or perhaps levels in Bloodrager (Abyssal) for the claws and Enlarge Person. Anybody care to make something better?

[Davor]

Fey Animal + Simple Druid Template.

You're welcome. :P

[Luke Schoppert]

Pick two:
-Two levels of fighter for the Improved Vital Strike every tyrannosaur deserves
-Giant+Advanced templates for massive ability score boosts and size increase
-Half-Dragon template for slightly less ridiculous ability scores, plus flight, breath weapon, energy immunity, and claws in case you want to put those disproportionately tiny arms to use.
-Fey template for some very nifty SLA's at the cost of a bit of melee power

Alternatively, going for four levels of Fighter can get you Greater Vital Strike. Not sure it's really worth it, compared to the opportunity to breathe fire/cast Irresistible Dance/be really huge

[GeneticDrift]

Mythic templates

Agile and divine,, then two levels of fighter for the vital strike buff.

Two actions a turn, mythic spells.

I would use arcane, but you will want/need? A headband or something to up charisma.

[Davor]

Okay, apparently I need to justify my choice. The simple druid template gives this Fey T-Rex access to Anti-life shell, but his reach is greater than it's radius, giving him almost total melee immunity; stoneskin; strongjaw for the damage bonus; geniekind for as-needed movement, plus, you know, all they Fey Animal stuff, including access to the Fly spell, Summon Nature's Ally VIII, Polymorph...

Sure, he doesn't deal as much damage per hit unbuffed, but... he also has access to 6TH LEVEL SPELLCASTING, plus the Fey Animal bonus spells. I think that pretty much speaks for itself.

[Avoron]

Fey Animal + Simple Druid is an excellent start.
Then add on the Young, Repeatedly-Drained, Mythic Agile, and Mythic Invincible templates.
Now we're talking deadly. But the real fun comes once you retrain some of its feats and skills to fit its role as a caster. Persistent Dazing Fire Snake, anyone?

On the other hand, if you're intent on staying martial, you'll almost certainly want to give it actual mythic ranks and Mythic Vital Strike.

[Kain Darkwind]

Luke, you can simply redo a T-Rex's feats to give it vital strike, no need to apply fighter levels. Skill Focus is a good candidate.

[Cuup]

2 levels of Fighter (for Imp Vital Strike (great idea, Luke)), and 4 Mythic Ranks. It gains DR 10/Mythic and +4 Str.

Feats:
Mythic Vital Strike - +26 on the Bite attack becomes +78 while Vital Striking!
Mythic Improved Initiative

Mythic Abilities:
-Simple Divine Spellcasting (Druid) - cherry pick some great Druid Spells (including Strong Jaw (18d6 with Imp Vital Strike!) and Greater Magic Fang (+5 Enhancement after his 2HD from 2 Fighter levels)
-Fickle Attack - bound to roll some 1's with 18 dice; now they're all 6's.
-Fast Healing
-Dual Initiative - I'm gonna be practical, and count this as 2 abilities.

OK, let's take a look: He's got some great defenses - DR 10/Mythic, and Fast Healing 5. But let's not fool ourselves; the star of the show is his new Bite attack, which, when Vital Striking with Strong Jaw and Greater Magic Fang active, deals 18d6+93 - and each 1 rolled counts as a 6. Not 100% sure how to calculate the average with this, but as best I can tell, it's something like 171. That's a pretty good Vital Strike. And he can do it twice in a round, having 2 turns and all. And I've only accounted for 7 of his 23 levels-worth of Druid spells he can have. At the end of the day, he could be flying, biting through an Anti-life Shell (cool idea, Davor!), and all other sorts of shenanigans!

[Davor]

Oh, we're using Mythic rules now? I wasn't aware we were CHEATING. :P

[alexd1976]

Half-Dragon, Advanced Template, Giant Template.

Wicked breath weapon, and a bite that does tons of damage... Plus, you know, flying T-Rex!

Also, they become sentient, which is just hilarious.

If you apply Half-Dragon 'first', then Advanced, you wind up with INT 8. :D

I used these in one of my previous games (PCs were level 20/10 Mythic) and these still posed a pretty good threat (in groups, mind you)...

[GeneticDrift]

I wouldnt go all in with mythic since the PCs are probably not mythic. Making hits insta kill isnt fun for anyone. CR is reigned in by average to hit and damage, this monster is ending up way to high. A cr 13 average dmg is 60.

I went mythic for the solo encounter to be a challenge. Freedom of movement, protection from good, mythic blessing of fervor...

[Cuup]

GeneticDrift wrote:

I wouldnt go all in with mythic since the PCs are probably not mythic. Making hits insta kill isnt fun for anyone. CR is reigned in by average to hit and damage, this monster is ending up way to high. A cr 13 average dmg is 60.

I went mythic for the solo encounter to be a challenge. Freedom of movement, protection from good, mythic blessing of fervor...

To be fair - the OP asked how deadly a CR 4 bump to a standard T-Rex could be, not to make a balanced CR 13 monster. But fair enough, maybe straight Mythic isn't supposed to be in this setting. I shall return with a cheat-free build.