For the yubel event could the new reward cards be the sacred beasts or rainbow dark dragon and advanced dark. she uses all of these and theyre not released yet
Just the Advanced Dark field spell, the monsters won't ever appear as they are literally just reskinned Crystal Beast. They literally don't have anything different from regular CBs, besides looks. So it's pointless putting them in.
Well there's Infernal Gainer, Prodigy and Edgy Bladege, then you have the fusions, 5 if i'm not mistaken and then the spells, Dark Fusion and Dark Calling, 10 card is not bad, they could even mix there the original E-Heros with Alt look
I doubt that Rainbow Dark Dragon will get released yet. Unless they redo the Yubel event and have possessed Jesse as a boss, I don't think its happening.
Which is funny, since Rainbow Overdragon lists Rainbow Dark Dragon as one of its tribute materials.
Considering the highlight of the Evil Heroes deck was Super Polymerization, that's not gonna happen. It would be over the top broken to use whatever your opponent has down for your tribute summon whenever the mood takes you.