Potemkin is the stongest character in the game. Using him, you can kill an opponent in as little as 20 seconds. If you are new, he is ok to use, just watch his speed. He is very slow.

Moves List

Mega Fist I - QCF+P
Mega Fist II - QCB+P
Sliding Head - QCF+S (This is an unblockable move if they are on the ground. If they are outside of the impact range, they will fall, but they will take no damage. They have three times the recovery time though, so try to deal damage by taking advantage of this.)
Hammer Fall - [B],F+HS (Potemkin can take one hit during this move and still continue it. Anything after that and the move will break as if he was hit.)
Potemkin Buster - HCB,F+P (close) (This move can be used as a counter. If Potemkin's swing to grab hits any physical attack within it's first half of the animation, before his hand passes his own body from your view, he will grab the opponent and use the Potemkin Buster on them. Also he can grab them at a longer range is they are dashing/running.)
Heat Knuckle - DPM+HS (anti-air only)
Heat Entend - HCB+HS during Heat Knuckle

Overdrive Attacks

Giganter - HCB,F+HS
Gigantic Bullet - HCFx2+P just after the Giganter is let out. (It's best to do this motion right after the last one.)
Heavenly Potemkin Buster - QCFx2+S (anti-air only)

Instant Kill

Press All 4 Buttons to activate the "Attack Mode" then while in it:
Magnum Opera - QCFx2+HS (close)

Combos

[B], HS, F+HS
This is a 2 hit combo coming from Potemkin. Be happy. FOr this, when you hit with the HS, be holding back to use a Hammer Fall right after the HS.

Guilty Gear Mode Changes

Slightly stronger. Higher Defense. Not much else.

Gold Form Changes

Potemkin becomes the slowest character in the game. He also has the ability to kill you within a few shots. He also now has the highest defense in the game. Not much else changed.