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You MUST give the opp time to play any doms after your ability finished. So they could play grapes, but since his ability was NOT negated they couldn't rescue ls.
If no good Enhancements are played this battle
That's not the right way to look at it. If Grapes is played right away, no good enhancements were played that battle. That triggers the ability to protect all Lost Souls from rescue, which is an ongoing ability that lasts until the end of the phase, which is more than this battle.