Full list of all 25 Serious Sam 3: BFE achievements worth 250 gamerscore. It takes around 15-20 hours to unlock all of the achievements in the base game.
The base game contains 20 achievements worth 200 Gamerscore, and there is 1 DLC pack containing 5 achievements worth 50 Gamerscore.
Smash 20 Kleers with the Sledgehammer.
Kill an enemy using the Mutilator.
Complete the single player campaign.
Awake the Guardian of Time.
Power up the Timelock.
Kill 20 enemies with the Minigun without releasing the trigger.
Solve the riddle of the Sphynx.
Secure the bird.
Kill at least 5 headless kamikazes in one explosion.
Rescue professor Stein. So to say.
Complete any level in single player.
Complete the game in single player on unmodified serious difficulty.
Perform all possible finishing moves in the game.
Find at least 50 secrets in single player.
Complete the campaign in cooperative with at least 2 players.
Decapitate a Khnum.
Blow a Major Biomechanoid into pieces.
Kill the kicked enemy while it is still in the air.
Rip Scrapjack's head off.
Find Sam's classic outfit.
Complete the Jewel of The Nile single player campaign.
Win a versus match.
Win 10 deathmatch games.
Score a total of 10 points in CTF matches.
Make at least 3 kills in one Instant Kill match.