Multiple instances of menace on the same creature are redundant.
2024-06-07
Once Dreamdrinker Vampire becomes blocked by a creature, giving it menace by putting one or more +1/+1 counters on it won't cause it to become unblocked.
2024-06-07
You can always activate an ability that will cause a creature to adapt. As that ability resolves, if the creature has a +1/+1 counter on it for any reason, you simply won't put any +1/+1 counters on it.
2024-06-07
If a creature somehow loses all of its +1/+1 counters, it can adapt again and get more +1/+1 counters.
: Adapt 1. (If this creature has no +1/+1 counters on it, put a +1/+1 counter on it.)