Building a Summoner as a tank?

[Firebug]

Ignoring Synthesist for the moment.

Well, they can eventually shift evolutions from their Eidolon to themselves, gain AC/Saves(+2 at 4, +4 at 12) while within the Eidolon's reach, and any damage that reduces them below 0 can be transferred over to the Eidolon instead (at 14).

They start with Light armor proficiency and can ignore arcane spell failure while in it. However, at higher levels, its probably more advantageous to do something like Deific Obedience(Arshea) #2 boon, Cha to AC as an Armor bonus. Summoners really only care about Charisma, so it should be sky-high.

Summoners have a pretty good buff list: Ablative Barrier, Blood Armor, Barkskin, Resist Energy, Wind Wall... just to look that their 2nd level spells only.

Its probably easier just to buff their Eidolon and use the Eidolon as the tank and the Summoner as the support, but it could happen. I've been in games with Summoners (both chained and unchained), and in one case they basically played their Eidolon (unchained Elemental) 'Dragon' as their character, and their Summoner as a poor human that they forced into servitude to (occasionally) buff them. Other than a decent Charisma (for uses of their SLA, and bonus spells) they don't really need stats, so you can afford good Con and Dex/whatever for AC. The same player also had another unchained Summoner who basically played 2 identical 'orcs' with greataxes using the Ancestor subtype for their Eidolon.

Basically, what do you mean by 'tank' and someone can probably make it work on any class.