One of the side effects of regeneration is that if the creature is untapped, it becomes tapped. That means if you hold back, you could block with your inspired creature, then cast Necrobite on it. Not only will that attacking creature face a likely death due to deathtouch, but if your blocker would be destroyed, the regeneration shield will save your creature, tap it, and when you untap during your untap step, you’ll get your inspired trigger. Pretty sneaky!
Let’s look at an example. Let’s say I cast a Pain Seer last turn. You, also looking for some inspiration, attack with your Pheres-Band Tromper, because you think I’d be foolish to block your creature. But I surprise you by blocking with my Seer, but also casting Necrobite on it. Not only will your creature die instead of living to see another untap step, but my Seer taps due to the regeneration, and I’m going to get my Seer trigger a turn earlier than you expected.
Do note that the regeneration shield has to be used up (i.e., the creature would need to be destroyed) in order for the creature to become tapped. You can’t just cast Necrobite on a creature at the end of your opponent’s turn on a creature and assume it will become tapped.
Today’s Rules Tip written by Nathan Long