Divine Luck

You call upon the gods, hoping you are in their favor. 

Roll a d100. The gods will respond to a d20 + religion check roll of 16 or more, and a natural 20 will give you advantage on the d100 roll. 

Allow DM to interpret the d100 roll as a transformation to your physical appearance. The effects may be temporary, permanent, painful, useful, or whatever they deem appropriate. 

Only cast once per long rest--at the risk of your own death. 

Example: d100 roll of 6, your heart may turn into a plum and you instantly die. A d100 roll of 98 could result in a pair of wings that you can fly with, no matter your bone density.