Whenever a creature an opponent controls dies, put a +1/+1 counter on Sephiroth
Its probably not doing a lot in 1v1 formats, but even getting a single plains out there is nice
As the final boss of the original Red and Blue games, the star of the first and arguably best Pokemon movie, and one of the most feared competitive battlers in every generation it has appeared in, Mewtwo carries a weight of cultural significance that very few Pokemon can match
This rule includes a player's own commander, which can deal combat damage to its owner if the commander is controlled by another player or if its combat damage gets redirected to that player
It adds variety to the constructed options and gives you the ability to play more powerful decks and true combos that are not an option in the current Standard
All of that said, Astrologians Planisphere keeps its buffs permanently something it has over the other Standard Prowess creatures, and triggers Prowess itself