precioustoasty-deactivated20170 asked: Although Demons and Angels can't get the spark naturally, is it possible for another planeswalker to give them their spark? Kind of how Venser gave Karn his spark?

Since angels and demons are manifestations of mana, they don’t have the right kind of essence or soul that allows one to be born with a planeswalker spark. So those creatures being planeswalkers violates the rules of the Multiverse. On the other hand, powerful magic sometimes makes it possible to violate the rules of the Multiverse. In a boundless Multiverse suffused with magic, what shouldn’t ever happen occaaaaaaaaaaaaasionally does.