Actually playing with him is enlightening as well: hes just so hard to stop
Drain synergies on Bastion of Remembrance, pingers like Thermo-Alchemist, and consistent noncombat damage from a card like Chandra, Awakened Inferno, spell doom for players that can't engage in combat
Everything from the Pokmon and Yu-Gi-Oh
This efficiency is extremely relevant against all the above-mentioned decks, since they try to be as explosive as possible to overwhelm the opponent before he manages to stabilize
Basically, the TLDR is that you can build an almost infinite number of really fun, solid, and competitive Commander decks for free with the help of the card-rental programs
This is because they are exiled with a Stash counter