The Rollercrusher Ride is a great answer to Aggro and go-wide decks in Standard
It's creatures-only, which is a lot worse than Teferi's Protection, but I think that's a Mount-Everest-level hill to climb and it's still a great choice
Card draw will always be a boon to any deck, and it helps that Greninja synergises well with some of the sets stronger water Pokmon such as Starmie V and Origin Forme Palkia VSTAR
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Basalt Monolith, Ashnod's Altar, and Paradox Engine are examples that made the list for their combo potential, and there are plenty of others that didnt make the list
As a 5-color commander, Azlask's color identity lets you include every single one of the other experience counter cards, and its generally useful activated ability synergizes well with all those extra ways to generate counters