Exile Eldritch Evolution
You can slow things down quite a bit with this creature around, and it has nice stats as a 3/2 first strike
Even a massive collection can be easily tamed with these boxes, and the player can use dividers to sort the cards by color, type, set or block of origin, and more
Im in no way insinuating this is able to compete at a cEDH table!) Ported over from the precon are Tournament Grounds, Godless Shrine, Temple of Silence, Command Tower, Arcane Signet, and Colossal Hammer
This means you're either giving up on the combat step or on stationing your permanent
Given the strong cachet of The Abyss, and how much better it is at the kitchen table as well, (especially in a Commander metagame heavy with flyers), the fact that The Abyss is running under $250 for a played copy, and under $150 for an Italian copy is just beyond me