Oversoul
The Tentacled One
Thumbs up on the new idea for the Shados. It removes the rules baggage attached to the type, prevents possibly degenerate effects (like the one I mentioned with Unnatural Selection), and leaves room for sundry other effects like having Shados that get +2/+2 for each other Shado and such...
Now about your other cards...
Duality is freaky. I can't tell whether it's safe or not, but I can't think of anything that would break it. Put it on a watch list or something, I guess.
Negation may be too good in the right deck. It is a hard counter for U. The drawback is extreme, but there are plenty of ways to nullify it. On the other hand, it is only a couterspell, which isn't broken...
Unruhe is either too good or a truly awesome card that would see a lot of use in black control decks. I'm going with the latter for now.
Everything else seems fine. Death Toll is multiplayer funnessity.
Now about your other cards...
Duality is freaky. I can't tell whether it's safe or not, but I can't think of anything that would break it. Put it on a watch list or something, I guess.
Negation may be too good in the right deck. It is a hard counter for U. The drawback is extreme, but there are plenty of ways to nullify it. On the other hand, it is only a couterspell, which isn't broken...
Unruhe is either too good or a truly awesome card that would see a lot of use in black control decks. I'm going with the latter for now.
Everything else seems fine. Death Toll is multiplayer funnessity.