Once per turn, when creatures with counters on them deal combat damage to a player, the player who controls Tidus can draw a card and proliferate (i.e., add an extra counter to creatures and permanents that already have them)
There are 8 in total: Yanma (shiny) Flareon (shiny) Magikarp (shiny) Gyarados (shiny) Vaporeon (shiny) Magnemite (shiny) Magneton (shiny) Jolteon (shiny) Misdreavus (shiny) Mankey (shiny) Primeape (shiny) Nidoran (shiny) Nidorina (shiny) Nidoqueen (shiny) Nidoran (shiny) Nidorino (shiny) Nidoking (shiny) Sneasel (shiny) Lickitung (shiny) Eevee (shiny) These are all the Pokmon shiny super rare cards in Wisdom of Sea and Sky
There are lots of typal Commander decks too, from Edgar Markovs vampires to Krenko, Mob Boss goblins
ID: 115384 (TCG-MTG-KNDCDUU) Tap or click above to open expanded view Sealed, unopened product
If you like Goblins, try out Swarming Goblins that gives you the chance to put between one to three Goblins onto the battlefield over and above the 4/3 creature you get to start with
While you have to put two cards back on top of your library, this isn't as much of a downside as you might think