_=2 (4x) weaknesses, -=a 4x weakness each, *=an 8x weakness
Add Forest's Curse:
Normal/(Grass)/Ice_
Normal/(Grass)/Dark_
Normal/(Grass)/Steel_
Fire/(Grass)/Bug_
(Grass)/Ice/Fighting_
(Grass)/Ice/Flying_
(Grass)/Ice/Psychic_
(Grass)/Ice/Bug--* (2 (4x) weaknesses + an 8x weakness)
(Grass)/Ice/Rock_
(Grass)/Ice/Dark--- (3 (4x) weaknesses)
(Grass)/Ice/Steel-* (a 4x weakness and an 8x weakness)
(Grass)/Ice/Fairy--- (3 (4x) weaknesses)
(Grass)/Fighting/Poison_
(Grass)/Fighting/Ground_
(Grass)/Fighting/Flying_
(Grass)/Fighting/Bug-* (a 4x weakness and an 8x weakness)
(Grass)/Fighting/Dragon--- (3 (4x) weaknesses)
(Grass)/Fighting/Dark_
(Grass)/Fighting/Fairy_
(Grass)/Poison/Bug_
(Grass)/Ground/Psychic_
(Grass)/Ground/Bug--- (3 (4x) weaknesses)
(Grass)/Ground/Dark_
(Grass)/Flying/Bug---- (4 (4x) weaknesses)
(Grass)/Flying/Fairy_
(Grass)/Psychic/Bug--- (3 (4x) weaknesses)
(Grass)/Psychic/Ghost_
(Grass)/Psychic/Dragon_
(Grass)/Bug/Ghost_
(Grass)/Bug/Dragon_
(Grass)/Bug/Dark--- (3 (4x) weaknesses)
(Grass)/Bug/Fairy--- (3 (4x) weaknesses)
(Grass)/Rock/Dark_
(Grass)/Dragon/Dark--- (3 (4x) weaknesses)
(Grass)/Dragon/Fairy_
(Grass)/Dark/Steel_
Source:
https://krlw890.github.io/pkdb-answers/type_combos.html