Fer singles, right?
Hex is a slightly gimmicky and unreliable thing to use, since its dependent on the opponent being statused, which might not always happen. And the way you have to inflict status effects is not very reilable at all (Hypnosis and Inferno are not accurate). Shadow Ball is generally the better attack here.
For Chandelure, this is a better set than what you got:
-Chandelure w/Choice Scarf
Nature: Modest
Ability: Flash Fire
EVs: 252 Special Attack, 252 Speed, 4 Defense
Moves: Fire Blast, Energy Ball, Shadow Ball, Hidden Power Fighting (if its Hidden Power isn't Fighting, Ground works ok too. If its not that either, throw in Psychic or something)
And Gengar:
-Gengar w/Gengarite
Nature: Timid
Ability: Levitate ---->Shadow Tag
EVs: 252 Special Attack, 252 Speed, 4 HP
Moves: Shadow Ball, Sludge Bomb, Destiny Bond, Focus Blast
Jellicent is a good Ghost type to add to your team for sure.
-Jellicent w/Leftovers
Nature: Bold/Calm
Ability: Water Absorb
EVs: 252 HP, 252 Defense or Special Defense (depending on which way you want it to go), 4 Special Attack
Moves: Scald, Will-o-Wisp/Toxic, Recover, Shadow Ball/Hex (Hex works in this case because Jellicent has a better way to status the enemy and can take hits unlike Gengar and Chandelure)
And I think Golurk gets Shadow Sneak? If it does, replace Shadow Punch with that; Golurk's slow, so its a nice way to get the jump on weakned enemies.
Not entirely sure what to do with your last slot...
Nah ンン
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