(Keep in mind this is before the D&D 50th Anniversary Secret Lair Drop coming August 29!) I think the quantity printed of the Lil Legends Lair is whats going to define the availability of this Festival in a Box
Ultros gives you a great way for those kinds of spells to interact with your opponents creatures and slow them down, giving you more time to cast awesome spells
Creature - Shapeshifter Wort, the Raidmother When Wort enters, create two 1/1 red and green Goblin Warrior creature tokens
Rounding out the massive drop are collections illustrated by prolific artist Jack Hughes - he portrays Planeswalkers and creatures in haute couture fashion - Weirdest Pets in the Multiverses oddly adorable critters, The Space Beyond the Stars four stellar-themed cards reminiscent of 1920s portrayals of the solar system, and four Galaxy foil-treatment lands in the Totally Spaced Out drop
While Pyromancers is better since you can use it from the graveyard, both cost five mana
I like it best in green decks that ramp out a bunch of 5+ cost threats, at which point Ugin lays waste to everything else (the ramp also helps play Ugin at a reasonable time)