Registeel

SteelShape of Steel, Light Metal

Level-up moves 12

Lv	Move	Type	Cat	Pow	Acc	PP
100	Iron Defense Phase 1 rotation Hardens the body's surface to sharply raise Defense.	Steel	Stat	—	—	15
100	Amnesia Phase 1 rotation Forgets about something and sharply raises Sp. Def.	Psychic	Stat	—	—	20
100	Hard Press Phase 1 rotation	Steel	Phys	100	100	10
100	Heavy Slam Phase 1 rotation	Steel	Phys	1	100	10
100	Flash Cannon Phase 1 rotation Releases a blast of light that may lower Sp. Def.	Steel	Spec	80	100	10
100	Iron Head Phase 2 rotation Slams the foe with a hard head. May cause flinching.	Steel	Phys	80	100	15
100	Earthquake Phase 2 rotation A powerful quake that hits all other POKéMON.	Ground	Phys	100	100	10
100	Flash Cannon Phase 2 rotation Releases a blast of light that may lower Sp. Def.	Steel	Spec	80	100	10
100	Body Press Phase 2 rotation Does more damage the higher the user's Def.	Fighting	Phys	80	100	10
100	Iron Head Phase 3 rotation Slams the foe with a hard head. May cause flinching.	Steel	Phys	80	100	15
100	Flash Cannon Phase 3 rotation Releases a blast of light that may lower Sp. Def.	Steel	Spec	80	100	10
100	Body Press Phase 3 rotation Does more damage the higher the user's Def.	Fighting	Phys	80	100	10

* a legal move, just moved to level-up · ** new to this game

This game's documentation doesn't publish TM compatibility, so none is listed here.

Area	Method	Level
Boss group — Legendary Golems	Boss (choose one of the group)	90–99, scales

Boss of the Legendary Golems group: one of the 5 you can choose to face when that group is drawn for an area. Fights in 3 phases, restoring to full HP at each phase change.
Its ability, Shape of Steel: Converts steel to HP.
Its ability, Light Metal: Halves weight.
Innates switch on as your boss count grows: Clear Body (Prevents ability reduction.) — from your 2nd boss win; Filter (Weakens “supereffective”.) — from your 4th; Steely Spirit (Boosts ally's Steel moves.) — from your 6th.
Reward for beating it: the ability Clear Body (Prevents ability reduction.).