Here is the full list of all 70 Serious Sam HD: The Second Encounter achievements.
Complete the game in single player on serious difficulty.
Complete The Grand Cathedral level on serious difficulty without dying or loading.
Accumulate a total of 100,001 enemy kills and frags combined.
Earn gold medals on all Survival levels in cooperative Survival.
Earn gold medals on all Survival levels in single player Survival.
Win a Beast Hunt match on all game levels.
Win 1000 Deathmatch games.
Win 100 My Burden matches with at least 3 players.
Win 100 Last Man Standing matches with at least 4 players.
Complete a Coin-op cooperative game on normal or higher difficulty.
Pick up at least 10 extra life items in Cooperative Coin-op game.
Pick up 100 gold coins in Coin-op Cooperative game.
Win a Team Beast Hunt match on any level with least 2 players on each team.
Win a Team Beast Hunt match on all game levels with least 2 players on each team.
Complete the game in single player by beating estimated time on each level.
Win 100 Last Team Standing matches with at least 2 players on each team.
Earn at least a bronze medal on any level in cooperative Survival.
Frag a total of 1337 players.
Frag 100 different players.
Frag 10 players without being killed in at least 4 player Instant Kill match.
Earn a round for your team in Last Team Standing game with at least 2 players on each team.
Win a Deathmatch Marathon.
Frag a total of 1000 players.
Win 100 Instant Kill matches.
Win an at least 4 player Deathmatch by reaching frag limit of at least 25 without dying.
Perform 4 frags with each being no more than 10 seconds apart from the previous frag in at least 4 player Deathmatch.
Frag all players in a single frag combo.
Win a CTF match with at least 2 players on each team.
Win 25 CTF matches with at least 2 players on each team.
Win one round in Last Man Standing game with at least 4 players.
Win one Team Deathmatch with at least 2 players on each team.
Win 100 Team Deathmatches with at least 2 players on each team.
Win one My Burden match with at least 3 players.
Hold the Burden for at least 10 minutes in My Burden match with at least 3 players.
Win a Beast Hunt match on any level.
Score a total of 100 points in CTF matches.
Win 100 deathmatch games.
Frag a total of 500 players.
Complete 100 Deathmatches.
Frag 100 players in a knife-to-knife fight.
Win 25 1-on-1 Deathmatches.
Earn at least a bronze medal on any level in single player Survival.
Find all secrets in single player.
Deliver the final blow to Mordekai with the Knife.
Perform 100 rocket jumps.
Win a Deathmatch.
Complete any level in at least 3 player cooperative game.
Kill 1000 enemies with the Laser gun.
Frag a total of 100 players.
Frag 25 players with a knife while having no more than 10 health left.
Frag 100 players with a knife.
Frag 100 players with a knife from behind.
Complete a Deathmatch with frag limit set to at least 200. (Frag limit must be reached!)
Frag the same player 5 times in a row in at least 4 player match.
Frag the same player 10 times during a single round in at least 4 player match.
Find at least 80 secrets in single player.
Kill 100 Harpies with the Sniper rifle.
Get all 3 Rocket launchers in Palenque - Sierra de Chiapas.
Find all 3 Cannons in Teotihuacan - The City of the Gods.
Complete a deathmatch game with at least 1 frag.
Burn 500 enemies to death.
Make at least 3 kills in one Instant Kill match.
Complete the game.
Complete the Medieval episode in single player or cooperative.
Kill 300 Kleers with the Cannon.
Find a secret under water.
Kill 50 Syrian Werebulls with a knife.
Complete the Persia episode in single player or cooperative.
Complete the South America episode in single player or cooperative.
Complete any level in single player.