Tales of Middle-earth is designed to be played in casual formats outside of Magics Standard tournament formatwhich means you cant throw down cards from it against up sets in the current rotation
In addition, all changelings are also gods, since they have all creature types
GW hints that you'll be able to return him to play using a rule called Reborn in Blood , but doesn't explain how this will work, just saying your army must have performed "sufficient slaughter." This could mean that Angron, or the World Eaters army as a whole, will be keeping a tally of kills that can be spent for in-game benefits - a mechanic we've seen in the Age of Sigmar Khorne Bloodbound army, and the Khorne Daemonkin from seventh edition 40k
That ability is pretty painful, but maybe you can make this card work in the Alakazam deck, or with the new stadium that removes all abilities
He chose to call it the Experimental Design Group