Here is the full list of all 25 Hammer time! achievements.
Get to level 25
Get to level 24
Get to level 23
Get to level 22
Get to level 21
Get to level 20
Get to level 19
Get to level 18
Get to level 17
Get to level 16
Get to level 15
Get to level 14
Get to level 13
Get to level 12
Get to level 11
Get to level 10
Get to level 9
Get to level 8
Get to level 7
Get to level 6
Get to level 5
Get to level 4
Get to level 3
Get to level 2
Get to level 1