I think I have seen a number of bug reports lately, which all revolves around creating supports and the game is unable to complete because there is no valid gem to instantiate the support gem.
There seems to be a need for fixing this issue in more general terms than we continually report the same fundamental bug with different cards triggering it.
I just had a freeze on the left node of Skoti bloodline, where a Tibalt, cosmic imposter card couldn’t find a valid gem when converting my instance to my opponent.