Registeel, the Stalwart Brain

{e}{e}, Put a shield counter onto target creature you control.

This creature gains the keywords of other Golems you control. If you control three or
more Golems, this creature gains +1/+1.

The final golem of the trio, Registeel is able to withstand immense pressures and intense temperatures, never cracking or melting against an onslaught of attacks.