Celestial Being has some skills unlocked right from the get-go, since they can't unlock them normally:

-Lawnmower
-Mega Finisher
-Reciprocate
-Reflect Bullets
-Deflect Bullets
-Block Breaker
-Mobile Accuracy
-Tac Sprint
-Head Leap

To activate Reciprocate, block an enemy's unarmed attack with having unarmed Guard, Advanced, then attack them.
Mega Finisher requires Power Finisher, and Critical hits to work.

Recommended skills: Timed kip-up for faster recovery slams, Special Strike for the ability to slam, and Shuriken Arc, for the ability to throw our modded weapons more efficiently.