Originally Posted by
Ness
As far as I know this is how it should play out:
1. Opponent plays Tidal Wave and both CT and DBK are killed.
2. On-death effects of respective allies resolve in the order they were summoned.
2a) If CT was summoned before DBK and there are at least 2 undead allies in the graveyard then CT will be returned to its owner's hand, consequently DBK will be the only ally left on the board when its on-death effect resolves and it will be returned as well.
2b) If DBK was summoned before CT then DBK's on-death effect will resolve first, consequently it will not be returned because CT is still on the board. If there are at least 2 undead allies in the graveyard then CT will be returned as usual.
3. Final phase of combat in which remaining killed allies on the board are sent to the graveyard. This phase occurs after on-death effects resolve so undead allies killed by Tidal Wave will not affect CT's ability.