It's a classic Commander card in that if a player really wants to roll the dice and not let you draw a card, they could get extremely lucky, and you mill lands off the top of your deck, but if you just so happen to send some high-value cards to the graveyard, your opponent is going to be hit for massive life damage out of nowhere
Plus, you just added a huge 5/7 flier
Mithril Coat is oh-so-close to being a strictly better Darksteel Plating, allowing you to flash in a way to make a legendary creature indestructible for just three mana
Even if your opponent is able to come back, you can still theoretically keep powering up more Meloettas and always take KOs until you win the game
After reading its effect, however, youll see that its totally niche at best and downright awful at worst
These three cards have been insane powerhouses and will most assuredly have forever homes in my list