Edited to remove misread. I was thinking it worked on ice of one subtype. Obviously that's not the case.
Alright, take 2, this time looking for one sub, not one subtype.
Ashigaru (only if there is just one card in HQ)
Brainstorm (only if there is just one card in grip)
Galahad (only if the corp doesn't reveal any other grail ice)
Hive (Only if they have scored 4 agenda points)
Information Overload (only if the runner has 1 tag)
Ireress (Only if the corp has just one bad pub)
It's a trap!
Komainu (Only if the runner has just one card in grip)
Lancelot (Only if the corp doesn't reveal any other grail ice)
Merlin (Only if the corp doesn't reveal any other grail ice)
News Hound (Only if there is no current in play)
NEXT Silver (Only if it is the only NEXT ice rezzed)
Salvage (Only if the corp has advanced it once)
Swarm (Only if the corp has advanced it once)
Tour Guide (Only if one asset is rezzed)
Tyrant (Only if the corp has advanced it once)
Universal Connectivity Fee
Wall of Static
Woodcutter (Only if the corp has advanced it once)