>>39791267Trevenant, Dhelmise, and Decidueye are all offensive Grass/Ghosts.
Trevenant is the original Grass/Ghost wallbreaker with moves like Wood Hammer letting it hit things hard with its respectable 110 Atk, and later started taking advantage of some of its other options like using Harvest to play around with berries and things like Leech Seed and Will o Wisp limiting its usual switch-ins.
Dhelmise is the better version of Trevenant, hitting things even harder with its 131 Atk and access to a third stab in Heavy Slam, Gyro Ball, or Anchor Shot.
Decidueye is decent all around, lacking the speed needed to be a sweeper but making up for it (not really) with priority moves like Shadow Sneak and Sucker Punch, utility moves like U-Turn and Roost, boosting moves like Swords Dance and even Nasty Plot, and a strong signature Z-move.
I think what you really want is a Grass/Ghost that can make up for its mediocre offensive and defensive typing, as well as mediocre stabs (Ghost types have notoriously awful physically attacking options).
