From Bulbapedia, the community-driven Pokémon encyclopedia.
Forest's Curse (Japanese: もりののろい Forest's Curse) is a non-damaging Grass-type move introduced in Generation VI. It is the signature move of Phantump and Trevenant.
Forest's Curse adds the Grass type to the target, in addition to the Pokémon's original type(s). If it is used against a dual-type Pokémon, that Pokémon will have three types at once. If the target already has an additional type added to it by Trick-or-Treat, that type is replaced with the Grass type.
Forest's Curse will fail if the target Pokémon is already Grass-type.
|| The user puts a forest curse on the target. Afflicted targets are now Grass type as well.
|Bold indicates a Pokémon gains STAB from this move.|
Italics indicates a Pokémon whose evolution or alternate form receives STAB from this move.
Certain Pokémon gain an 8x weakness to a type when affected by Forest's Curse. This occurs when a dual-type Pokémon has a 4x weakness to a type to which the Grass-type is weak (4x doubled by Grass weakness = 8x). This is currently the only way for a Pokémon to have an 8x weakness.
Following is a list of Pokémon affected this way by Forest's Curse and the types to which they would have an 8x weakness:
Mega Rayquaza would also have an 8x weakness to Ice-type moves if its Delta Stream ability were somehow suppressed.
Currently, no Bug/Ice-type or Ice/Steel-type Pokémon are known to exist, but if they did, they would have 8x weakness to Fire-type moves when affected by this move.
In other languages