Here is the full list of all 34 Screencheat achievements.
Win a round without ever missing a shot on Temple
Get 3 kills whilst bouncing on the floating cushions.
Play 20 rounds in a row in Party Mode
Kill 5 players from the moving platforms on Steeple
Kill an Opponent inside a vent on the Manor
Win a round on Ascension in less than 30 seconds with the default mode settings
Win a round of Murder Mystery without being killed
Kill an opponent inside the center tunnel on Loop
Get a Gold medal on all training missions.
Get a Bronze medal or higher on all training missions.
Get a Silver medal or higher on all training missions.
Reach level 25
Spend 10 seconds off the ground without dying on Holy Mountain
Kill an opponent through multiple objects with the wall_Hacker
Kill 1 opponent from each coloured area in Helix
Spend over 75% of a round charging with the Hobby Horse
Get 4 kills without reloading the Revolver Rifle
Get a quad kill or more with a single Chefolet ball
Get 1 kill with each weapon in a round
Harpoon 2 players in one shot with the Trappeur
Fire 50 grenades in Hill Campers and win
Get a mutli-kill with a projectile weapon through a vent
Play a perfect round of deathmatch with the Blunderbuss
Kill someone in the hill when they have 1 second to win
Get a multi-kill from beyond the grave with the Bearbomb
Kill 5 Opponents from on top of the dinosaur in the Museum
Get a quad-kill including yourself
Get a double kill with a returning Sörgeån
Get a multi-kill in One Shot
Reach level 5
Kill 3 opponents from behind with the Candelabra
Stay in one place in the Garden for 1 minute
Play 5 games with 4 local players
Reach level 50