I think Mister Fantastic is the strongest, because we love drawing cards and there are a LOT of triggered abilities worth copying twice
Although clearly inspired by other games of its kind, the uniquenesses of the One Piece Card Game shine through
And if you think everyone now having Beasts or Elephants is humorous, just wait till the table gets to roll the dice repeatedly with seven copies of Chaos WarpChaos Warp resolving
Sheltered by Ghosts is excellent, and its a bit surprising to see it at only uncommon
After that, if time allows, I will either add more and more details or even redraw some of the shapes from scratch
In spellslinger-heavy builds, think Izzet or Jeskai Control, effectively doubling your mana output for removal and draw spells while threatening massive bombs like Jeskai Revelation is genuinely terrifying for opponents