Konami keeps the chars to be released after another worlds open up to sustain the game for longer time period. Stop whining & complaining, scrub. Also for you ungrateful f2p swines who hate Scud so much: He designed to be secret char with obscured unlocking condition for a reason. Nobody force you to unlock this "useless" gem source.
I've been wanting Rebecca since the beginning. Seems unlikely now but she could have more gem dragons and fire princess. Maybe Diamond Head Dragon from the anime. Duke would be great (maybe in DSOD world) and his ace is a real card now.