I think Retrodes should be put in all lvls, everywhere. And those lvls should be used to replace all other lvls. Especially in T3 and especially in concrete jungle. Because with Retrodes in concrete jungle, we wouldn't need any other lvls or mobs anywhere. We'd have everything we need: Retrode concrete jungle everywhere. Wouldn't that be fun?
And don't forget the beast arena. We need more Retrodes in beast arena, because beasts just aren't beastly enough. Unless of course, beast arenas get replaced with Retrode concrete jungle. Then there'd be no need for that.
You ARE kidding, right?