The 5th Anniversary Update Title update for Alien Swarm: Reactive Drop has 19 achievements.
Complete the Nam Humanum campaign on Easy difficulty or harder.
Complete the Nam Humanum campaign on Normal difficulty or harder.
Complete the Nam Humanum campaign on Hard difficulty or harder.
Complete the Nam Humanum campaign on Insane difficulty or harder.
Complete the Nam Humanum campaign on Brutal difficulty.
Complete Logistics Area within 1:10 on Normal difficulty or harder without any marines dying.
Complete Platform XVII within 3:02 on Normal difficulty or harder without any marines dying.
Complete Groundwork Labs within 2:25 on Normal difficulty or harder without any marines dying.
Complete the Nam Humanum campaign on Normal difficulty or harder without any marines dying.
In Groundwork Labs, upload prohibited data to the ship.
Complete the BioGen Corporation campaign on Easy difficulty or harder.
Complete the BioGen Corporation campaign on Normal difficulty or harder.
Complete the BioGen Corporation campaign on Hard difficulty or harder.
Complete the BioGen Corporation campaign on Insane difficulty or harder.
Complete the BioGen Corporation campaign on Brutal difficulty.
Complete Operation x5 within 3:28 on Normal difficulty or harder without any marines dying.
Complete Invisible Threat within 1:13 on Normal difficulty or harder without any marines dying.
Complete BioGen Labs within 4:14 on Normal difficulty or harder without any marines dying.
Complete the BioGen Corporation campaign on Normal difficulty or harder without any marines dying.