This is a long rambly way of saying that Erebos, Bleak-Hearted is a very strong Sacrifice commander, but he'll end up being better in the 99 of even stronger Sacrifice commanders, of which there are a crapton at this point
In a perfect turn, the creature equipped with this could gain four or more counters depending on the spells cast
We also get to mill ourselves, which, in the right deck or even the right format, is akin to drawing three cards anyway
Updated March 23, 2023 by Ryan Hay: The very silly Unfinity has been out for a bit, giving players and collectors all the time they need to open packs and chase the cards they need
If you have no other cards in hand, you must discard one of the cards you return to your hand
Remember that if you want unique backs for the cards in your deck, you'll need to create a mirroring deck with those back designs and then check the Unique Backs option in the import dialog