Krenko, Mob Boss

{T}: Create X 1/1 red Goblin creature tokens, where X is the number of Goblins you control.

Scrap Welder

{T}, Sacrifice an artifact with mana value X: Return target artifact card with mana value less than X from your graveyard to the battlefield. It gains haste until end of turn.

Gleeful Demolition

Destroy target artifact. If you controlled that artifact, create three 1/1 red Phyrexian Goblin creature tokens.

Exuberant Fuseling

Trample
This creature gets +1/+0 for each oil counter on it.
When this creature enters and whenever another creature or artifact you control is put into a graveyard from the battlefield, put an oil counter on this creature.