Axl

Axl is the first intended optional boss in Grounded 2, a colossal tarantula that dwarfs every other bug in the park, found at the Battlefield 1992 landmark up in Pine Hill. His fight is summoned with a Poached Roach Roast and seals you in until one of you dies. The trick is his 75% resistance to all damage: normal hits barely scratch him, so you have to strike the scar on his abdomen to do real harm.