DK Barrel, Buddy Barrel

Kong family
DK Barrel can be your commander.
Commanders you control have "You can have
three commanders if all three have kong family.)
{t}, Sacrifice DK Barrel: Exile a commander from
your command zone. For as long as it is exiled
this way, it has "When a commander you control
would be put into the graveyard, you may cast
this card without paying its mana cost."