Day 3 of Modern Horizons 2 spoilers features callbacks, Suspend spells
Modern Horizons 2 is becoming a series that allows Wizards of the Coast to take risks with card design and bring back mechanics that are unlikely to ever make it into a Standard legal set. This is because Modern Horizons 2 is directly printed into Modern, skipping Standard legality.
Suspend, Storm, and Vanishing are a handful of the older Magic mechanics that are returning in the upcoming set. Wizards also uses Modern Horizons to make references on older cards and add Easter eggs for longtime fans.