>>13260820A part of Gamefreak's 'balance' is in move distribution.
Gengar has the highest Special Attack and Speed of all ghosts, and has no setup moves.
Froslass has Speed and Spikes, and no setup moves.
Mismagius has average Special stats across the board, and has both Calm Mind and Nasty Plot.
It's not a hard rule, but you can find similar trends amongst other moves and in types according to stats.
Also, being able to switch in/ignore EQ/Ground weakness for Gengar is more valuable than the few situations where its support moves are outsped.
