The effectiveness of the next card from Dark Ascension is hard to judge without further testing:
The first time I read the card I thought it read: Target creature gains deathtouch until end of turn and all creatures able to block target creature must do so. I thought this was literally a "deathtouch + lure" combo card with flashback. In truth, I think this card is much worse than it pretends to be. In essence, it's a "fight" card without the "fight" keyword... but much worse.
Just like Tribute to Hunger actually reads: Destroy target opponent's worst creature. Deadly Allure actually reads: Choose a creature you control and target opponent chooses a creature he or she controls. The chosen creatures fight.
Do you see what I'm saying?
Deadly Allure is actually a worse version of Prey Upon in disguise where your opponent chooses their creature instead of you. The fact that it has flashback is its only saving grace.
It seems to me that if this card is going to be used at all, it's going to be in a black/green tempo deck. Because Deadly Allure has flashback, this type of deck would be able to deal an additional beating. And if I had to pair it with a single card, it actually works well with today's other previewed card: Predator Ooze. The deathtouch will ensure the ooze grows at double the rate and the indestructibility keeps it alive.