This can singlehandedly make you win games by using it when the opponent has a lot of cards in their hand or when it seems like they're preparing for a game-ending turn
Returning to your hand nearly any creature in your graveyard (not just one of the four you just milled) and conveniently adding planeswalkers as one of its gravedigging targets makes Overlord of the Balemurk very powerful
If you do play this goblin, be sure to include Krark's Thumb
Called By The Grave is a Quick-Play Spell card, which means the turn player can play it from their hand at just about any point during their turn, including the Battle Phase, or flip it on the opposing player's turn like a Trap card
It popped up again with the Commander Legends: Battle for Baldur's Gate commander decks in 2022, especially with the white-black Party Time deck focusing specifically on the mechanic
Its probably more than you own in your collection, and getting your hands on a box early on seems like Christmas morning