Yes — co-op and PvP. Alien Swarm: Reactive Drop is a co-op horde shooter game released in 2017, 95% positive on Steam (22,649 reviews), with 179 playing right now. Free on Steam.
Co-operative top-down shooter game available for free. An epic bug hunt featuring a unique blend of co-op play and squad-level tactics.
Steam's own category list for the game, as of 2026-09-09. "Not listed" means the store page does not claim that mode; community mods or Remote Play can still add it.
Steam tags: Twin Stick Shooter, PvE, Top-Down Shooter, Co-op, Class-Based, Third-Person Shooter, Aliens, Level Editor
Ready Up compares two Steam libraries and shows every multiplayer game you both have — including whether Alien Swarm: Reactive Drop is one of them — then helps you pick tonight's game with a weighted roll or a bracket.
Or open the Steam store page.
Tired of Alien Swarm: Reactive Drop? The Swap tab finds the closest unowned games of the same type that are newer or rated higher.
Ready Up is a free tool: enter two Steam usernames and it lists the multiplayer games you both own, runs a bracket to pick one, and suggests new co-op games that fit how you both play. Ratings, tags and player counts from Steam and SteamSpy; page updated 2026-09-23. Powered by Steam — not affiliated with or endorsed by Valve Corporation or Microsoft. Ready Up is a Somebody Decide program. How the data works · Legal & privacy · All types · Game Pass