Decks with plenty of ways to get cards in the graveyardtypically an abundance of fetch lands and cheap interactive spellscant get enough of this overpowered giant
Darksteel Colossus is the best at what he does: Having no drawbacks, being very big and very hard to stop
He will hopefully be a fun midrange mono-red commander and might well be our first great burn commander but not at a competitive level
You can play it in Commander as well, where its occasionally used in top dragon Commander decks with heavy hitters like Lathliss, Dragon Queen and Archwing Dragon
I personally enjoy playing it with Kellan, Inquisitive Prodigy since you can cast the adventure on turn 2, which mitigates the companion's primary weakness
Even though it retains the counters, it becomes a new object with no relation to its last existence in its previous zone