It's cool
Like Mark Rosewater, I don't expect Outlast to make a large-scale return in any future set any time soon, either
Metamorphosis can be used not only to summon Thousand-Eyes Restrict but also with high level monsters to summon powerful fusions like Gatling Dragon, Ryu Senshi, and King Dragun
[6] For a 360-card cube, heres a good distribution: 250 cards, with 50 for each color 50 red, 50 green, 50 black, 50 white, 50 blue 50 multicolored cards 5 each for the 10 color pairs 30 artifacts If you include a mono-brown archetype, consider doubling this number (at least) and trimming on the individual colors, since anyone can draft colorless cards
Brothers of Fire requires a stronger commitment to red, however, which might limit the decks you put it in
Decks that can easily summon Fiend and Rock-Type monsters would find Evil HERO Dark Gaia useful for its high ATK potential and the ability to switch defense position monsters to attack position