One big bonus to this type of set is every card can appear in any featured rarity
I would rather keep brain space and game changer space free for other legendary creatures perhaps on their own separate Commander-specific Game Changer list but all in all this guy just makes a ton of mana and gives you a restrictive outlet for you hes not even the most offensive mana-related Commander on the Gamechanger list
Blue decks might already be tempted to play something like Vedalken Orrery or Leyline of Anticipation
There are no combos to be countered or key pieces to be knocked out, just build up your sea horrors and crash into them over and over again until they die
It has two other forms: White Kyurem and Black Kyurem, which are activated by fusing it with Reshiram or Zekrom, respectively
Keep your answer to the above situation in your head for now (and remember that Gaston starts with a G, like Glory Seeker, and Belle starts with a B, like Bronze Sable) and let's keep moving on