You draw a card, get some lands, and even put cards in the graveyard to Regrowth later
That $8 price tag is almost entirely due to low supply, because any foil rare from that era would be worth at least $20 by now if it saw even a little bit of Commander play
However, Korvold adds great value to each sacrifice made by its controller, as whenever they sacrifice a permanent, a +1/+1 counter is put on Korvold and its controller draws a card
A format with problematic issues is more than likely not a good time to try for an unban
(Enter the first room or advance to the next room.) Create Undead Whenever you complete a dungeon, return target creature card from your graveyard to the battlefield
You can spend a mana to make a Wizard copy for everything that arrives and then that's in play or in the Command Zone too