Appearances aside, this Gengar is incredibly rare, as NM copies are rarely available on TCGPlayer, with no sales recorded for the first-edition Holo version of this card in recent times
The Proliferate upside is nice, as bouncing something expensive is usually the best thing to do to get the most tempo, but if you have enough counters around, or you feel the need to fire it off early, you get some upside This is trying to do an impression of Icy Manipulator and its doing a pretty solid job
Additionally, creatures like Orcish Lumberjack and Sylvan Safekeeper can provide powerful sacrifice outlets to fuel Hearthhull and the Devil as well
This kind of move, usually called "Hydro Pump", has been seen on water type pokemon cards since some of the earliest sets featuring the very first water starter line
that role was meant for Clefairy - but 'twas Pikachu that won the hearts of a global audience
Prompt Guidance allows you to control the creativity of the result