Games like Rise of the Wool Ball

If you finished Rise of the Wool Ball, the closest matches are Hot Dogs, Horseshoes & Hand Grenades, Serious Sam: The First Encounter, Alien Rage: Unlimited, Ghost in the Shell: Stand Alone Complex - First Assault Online and A Grande Bagunça Espacial: The Big Space Mess. All 9 share its shooter genre and are ranked by how closely their themes and modes overlap.