Iron Skin is K-9000's starting Amigo ability: the robot dog takes less damage from bullets and is immune to poison and fire. It makes him the toughest Amigo to keep standing.
K-9000 shrugs off a good share of gunfire and ignores status effects that hurt other Amigos. You can send him into a messy base fight without constantly reviving him.
Yes, especially if you use fire or poison weapons that would otherwise burn your own Amigo.
Ancient Survivor
Guapo recovers health over time and revives himself after being downed in combat.
Angrier Bird
Chicharrón's Angry Bird attack knocks enemies to the ground.
Angry Bird
Chicharrón launches himself at an enemy from a distance.
Attention-Seeker
Chorizo distracts enemies so you can sneak past or take them down.