Here is the full list of all 27 Slam Bolt Scrappers achievements.
Beat all campaign levels on expert difficulty
Beat all the hidden campaign levels
Beat 1000 grubs
Beat 100 demon cavalry
Beat Mountain Top 1 without taking any damage
Beat Skyscraper without dying
Steal a weapon of size 8x8 or bigger
Win a 1v2 battle against 2 Hard CPs
Play 100 Battle Mode Matches
Play 50 Battle Mode Matches
Win with only a 2x2 turret left in your tower
Knock out 20 opponents without dying
Play 20 Battle Mode matches
Steal your way to victory
Defeat a CP opponent in 1v1 battle before they can drop any blocks.
Play 5 Battle Mode matches
Win a level without killing any baddies
Win a match using beverage mode controls
Watch the entire credits. You're a true fan!
Win a match with only ping pong weapons
Build a 10x10 weapon (on any level other than Mega Blocks)
Play a Battle Mode match
Beat the Campaign
Get past the enemy hoard in Armageddon without dying
Beat Downtown 4: The Skyscraper
Beat Mountain Top 1
Beat all tutorial levels