The Drilldozer

When The Drilldozer deals combat damage to an
opponent, sacrifice it, create a tapped colorless
artifact token named Ommoran Heartstone Core
with Indestructible, Hexproof and
"{t}: Add {w}{w}{r}{r}", and create a colorless
artifact token named Dotty's Head with "Tap
four untapped dwarves you control: Return
Dotty's Head to your hand and draw four cards".
Crew 6
The Drilldozer can be your commander.