Azlask, the Swelling Scourge Azlask, the Swelling Scourge is pretty easy to trigger and gain experience, because it works on your colorless artifact creatures too, and turns aggressive dudes like Gingerbrute into fuel for your endgame
Elvish Archdruid, Priest of Titania, Circle of Dreams Druid its not uncommon to see these creatures tapping for 5 or more mana, which is a lot of power to add to a mana dork, and it can make them relevant threats later in the game
Sometimes it can be good to sacrifice a cheap location just to stop your opponent from earning lore on their turn, especially if you're going to be able to follow up with Genie or Elsa's Ice Palace to keep that exerted character exerted
Now planes are connected in strange ways, heroes are celebrating and mourning, and many Planeswalkers changed, losing their power to step between planes