Here is the full list of all 17 Temporal Temple achievements.
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Unlock Dan
Unlock Mary
You found it!
Use the chest three times in a single run
Jump 69 times in a single run
Unlock Big Tam
Unlock Jakarta
Die 25 times
Unlock Bone Boy
Kill a haunted enemy
Kill five Big Guys in a single run
Purchase a weapon from the chest
Last over 60 seconds in a single run
Use the Healing Shrine to recover health
Purchase an item from the shop
Last at least 30 seconds in a single run