*Still waits for the villains to try working together in order to win.*



aaaannnddd a thought just flew in my head.



Remember sombra's horn fragment? Well, what if, let's say, it landed in the snow of a mountain or something, and somepony skiing fell and scratched themselves on the hidden horn fragment? Would that mean that the horn would turn into a shadow or something and enter the pony's wound, corrupting said pony? And it would go on, getting others corrupted someway, or something, in order to gain enough power to use the crystal heart to revive Sombra or something?



And with the power the corrupted acquired, they plan to give it to Sombra to immediately bring back his full powers, instead of having to wait until he's rested?



I'll just go now...