In practice, Wrecking Ball Arm allows for any of your creatures to experience what it's like to be a Greater SandwurmGreater Sandwurm, which is powerful enough if you're equipping it to a legendary creature
For example, if you control Laughing Jasper Flint and Vial Smasher, Gleeful Grenadier, having a creature an opponent owns that normally isn't an outlaw enter the battlefield under your control will cause Vial Smasher's ability to trigger
There are so many great ETBs these days, so youll often just be buying something back in addition to bouncing another creature and drawing a card
Death Toll decklist for Duskmourn Commander Giving Deathtouch to Winter, Cynical Opportunist provides stability while you put together graveyard combos and take advantage of the MTG Delirium mechanic
This build will most likely go under the radar, so you need to be smart about who youre attacking and what youre saying not to paint a target on your back
It reminds me of Wizards of the Coasts older Commander precons, which were often more like two or three half-decks in a trenchcoat (the idea being that players would play a few games, get a feel for which mechanics they liked and then start swapping in cards to emphasize that part of the deck)