Full list of all 28 Windowkill achievements.
The base game contains 22 achievements, and there is 1 DLC pack containing 6 achievements.
kill an orb array as zephyr
beat timed mode as :)
kill ???
kill every boss
kill 98 bosses
get lv. 4 halt
survive for 2 minutes without shooting the window as bastion
hold 8 stars at once
obliterate a star
kill 10 spikers
collect a 1000+ value coin
get lv. 10 multishot
have 50 health
get 40,000 coins in one run
beat timed mode
buy 100 shop items
survive for 20 minutes
?
manifest 50 items
unlock everything
get a x4 multiplier
block 200 bullets
kill 2 bosses at once during halt
die to slime trail
kill wyrm without causing a split
survive for 4 minutes without collecting a coin
get lv. 4 detach