Here is the full list of all 25 Looterkings achievements.
Won your first game of Goblin Ball
You scored your first goal. Congratulations!
Used the special abilities for the first time
Kill the Elven Prince in Level 5
Steal 250 Gold from fellow goblins.
Fall into hot lava. And die miserably.
Stun a fellow goblin with a mushroom.
Carry a fellow goblin
Ride a fellow goblin.
Resurrect 50 fellow goblins.
Get resurrected 50 times by a fellow goblin.
Kill 100 Enemies while in favor of SHAMAN.
Kill 100 Enemies while in favor of JERK.
Kill 100 Enemies while in favor of BRUISER.
Kill 100 Enemies while in favor of BASTARD.
Steal 1000 Gold from fellow goblins.
Steal 10.000 Gold from fellow goblins.
Kill 150 Enemies in berserk mode.
Kill 1000 skeleton warriors.
Spend 100.000 Gold on equipment in the goblin-shop.
Pretty sure referees would object to your creativity
Win 100 GoblinBall-Matches
Got every GoblinBall team sticker
Scored 75 or more times