This is because it's a 5-White 5/5 creature with a reanimation effect and an ability that puts +1/+1 counters on it every time damage is dealt to it, which is also prevented
Obviously if you find a shell without blue you cant play Polymorph, but if you are playing blue then I think it mostly comes down to if youre playing with Force of Negation or not
I'm out of the loop, but my friend had a nasty deck years ago with Phyrexian Obliterator, though it doesn't necessarily add value beyond itself like some of your other choices (Dauthi Voidwalker looks wild)
So you can equip a creature with the Paladin ability, but youll need to attach the reconfigure card to another creature first before being able to unattach the creature via reconfigure
As such, a card that wins you the game for having 40 life handily, the exact life total you start with in the Commander format wasnt thought to be overly pushed upon its debut
We use a non-abrasive rubber to move the card from the hopper to the chamber