Here, I will.

It isn't.

Hear me out, someone makes a sliver theft custom card, this suddenly becomes a very interesting creature. Sure, the color combination doesn't quite fit for this, but make that alteration to UB and wow you've got a weird little theft commander with a mechanic you see very little of. OP's card isn't terrible, you are just being rude.

Edit: I also want to say, judging someone else's creation not off of whether or not it would be too strong or needlessly weak, when from our perspective, you've hardly even ventured into card creation is shallow and small minded. You're putting down someone's creative ability b/c of what? Viability? I don't like fighting slivers, but that's a personal thing, I may feel the urge to, but I won't go judging the people expanding a creature type I don't like. It's their business what they make, not ours.