If youre using Ursula, Deceiver of All, to sing song cards costing three or less ink - such as Friends on the Other Side and Bear Necessities - then youll be able to perform their abilities twice in succession, which is possibly game changing
Unless the card says otherwise, you don't have to wait until your turn to activate an activated ability
One common through-line that I feel seemed to be the case throughout the set was the value of Torbran, Thane of Red Fell - this Dwarf is just very good at making some of the best cards in this set seem better: I expect to see token strategies, fast aggressive strategies, and burn-based strategies all get a bump from the cards in this set
If your opponent doesn't have an answer for Bolas pretty soon after he is played, then the game is going to slip from their fingers relatively quickly
It offers a chance to get in on the ground floor of a new, potentially beloved corner of the Multiverse