(Treat it and anything attached to it as though they don't exist until your next turn.) Whenever King of the Oathbreakers or another Spirit you control phases in, create a tapped 1/1 white Spirit creature token with flying
(I also love that artwork too!) Oh, and this was true of the first Portal set as well as many strong cards from it were reprinted almost immediately, like Gravedigger, Thundermare, Alabaster Dragon, Raging Goblin, or Natural Spring as well as draft standards like Mind Rot, Volcanic Hammer, or Breath of Life which was a cheaper version of Resurrection in White, and then others that were reprinted here and there later, like the afore-mentioned Ebon Dragon, or Endless Cockroaches and Gift of Estates
Between the two Commanders, Tidus will work better in a counter-themed deck
Good all around, just better in certain places