The first result is the ability to expand the deck combos by acting as a flood-gate
(6/8/2018) Assist allows another player to pay for any amount of generic mana
ST20-12 U Tamer Sora Takenouchi & Kari Kamiya Color Red Yellow Cost 3 Type ADVENTURE Card Text 1 [Effect] [Start of Your Main Phase] If you have a Digimon with the [ADVENTURE] trait, gain 1 memory
Cloak sees play to this day, and this very similar card is probably going to see play as well
Whenever you cast a white permanent spell, create a 1/1 white Soldier creature token
Aces Baseball Bat Source | Adric, Mathematical Genius Source Alistair, the Brigadier Source | Banish to Another Universe Source Barbara Wright Source | Bessie, the Doctors Roadster Source Displaced Dinosaurs Source | Duggan, Private Detective Source Explore Source | Five Hundred Year Diary Source Heroic Intervention Source | Ian Chesterton Source Leela, Sevateem Warrior Source | Nyssa of Traken Source Romana II Source | Sergeant John Benton Source Swords to Plowshares Source | The Five Doctors Source The Sea Devils Source | Three Visits Source Traverse Eternity Source | Vrestin, Menoptra Leader Source The reprints with new Doctor Who-themed art can be seen below in screenshots from the deck reveal video
