Spidey

has 400/1080 (Min/Max) units of health and has an Acid spit attack dealing 50/135 (Min/Max) units of damage. Acid weapons cause 100% of their damage against flesh targets and 130% of their damage against shielded targets.

can be acquired for 2000 via a random offer when you are between levels 27 and 37.

Training
A partner's rank can be upgraded at the Training Range, increasing the partner's health and attack damage.