Forest's Curse / Trick - Or - Treat / Soak
Forest's Curse is a move that attaches the Grass type to a Pokemon. Trick-Or-Treat adds Ghost type. Soak makes the Pokemon a pure Water type, giving Pokemon only two weaknesses. For Soak then, any Pokemon with 3 or more weaknesses now has only 2 with resists to Fire, Water, Ice and Steel. Here are type combinations that gain resistances and no more weaknesses without having an ability that gives type immunities:
Fire-Electric (Rotom-H | Forest's Curse)
Fire-Rock (Macargo | Forest's Curse)
Normal-Fighting (Meloetta-P | Trick-Or-Treat)
Any Type (except Psychic and Ghost) -Dark (Houndour Line, Carvanha Line, Crawdaunt, Greninja, Gyarados-Meaga, Nuzleaf, Shiftry, Cacturne, Sneasel Line, Scraggy Line, Pangoro, Stunky Line, Drapion, Sandile Line, Murkrow Line, Vullaby Line, Yveltal, | Trick-Or-Treat)
Fairy-Normal (Igglybuff Line, Azurill | Trick-Or-Treat)
Here are the type combinations that gain resistances and no more weaknesses with the abilities Sap Sipper, Motor Drive, Flash Fire, Water Absorb, Thick Fat, and either Levitate or the item Air Balloon under the effect of Forest's Curse or Trick-Or-Treat:
Thick Fat
Electric-Ghost (Rotom | Forest's Curse)
Electric-Fairy (Dedenne | Forest's Curse)
Rock-Steel (Aron Line, Shieldon Line, Probopass | Forest's Curse)
Dragon-Steel (Dialga | Forest's Curse)
Also,
All Electric, Poison, Fire, Steel and Rock Pokemon with a type that doesn't resist Ground lose a weakness when given Levitate.
All Steel, Grass, Bug and Ice Pokemon with a type that doesn't resist Fire lose a weakness when given Flash Fire.
All Water, Ground and Rock Pokemon with a type that doesn't resist Grass lose a weakness when given Sap Sipper.
All Fire, Ground and Rock Pokemon with a type that doesn't resist Water lose a weakness when given Storm Drain/Water Absorb.
All Water and Flying Pokemon with a type that doesn't resist Electric lose a weakness when given Volt Absorb/Motor Drive.
