It doesn't matter much outside of Tarkir: Dragonstom cards
Exile the tokens at end of combat.) The term "defending player" in the myriad rules (or any other ability of an attacking creature) refers to the player the creature with myriad was attacking at the time it became an attacking creature this combat, or the controller of the planeswalker or protector of the battle the creature was attacking at the time it became an attacking creature this combat
Rebellion Rising is still a fun-looking build if you prefer to do a lot of attacking or create big board states
(Whenever a creature with myriad attacks, for each opponent other than defending player, you may create a token that's a copy of that creature that's tapped and attacking that player or a planeswalker they control Exile the tokens at end of combat.)
Scuttlegator Scuttlegator is below rate every step of the way
Personally, I think the core sets have gotten better and better ever since Wizards decided to include new cards instead of just a collection of reruns, and this one is probably my favorite one so far M13 was marred by what Omniscience means for the game, and before that there were Titans