Every act in STS2 offers two route variants. Your act-1 choice affects enemy pools, events, and bosses for the rest of the act.
What changes between paths
Enemy types differ: Overgrowth favors flora-aligned enemies; Underdocks emphasizes mechanical and underground foes.
Events are path-specific. Some positive events only appear in one branch.
Boss pool overlaps partially β each path has one unique boss and one shared option.
Strategic consideration
A deck good vs Overgrowth enemies may struggle on Underdocks and vice versa. When the reward is known, pick the path your deck handles better.
Elite fights also vary between paths; scout the most dangerous elite for your current build before committing.