Fire type has the very strongest advantage over Grass type Pokemon
GRASS
A Fire-type Pokemon can deal 2x the damage to Grass, Ice, Bug, and Steel-type Pokemon.
Grass-type Pokemon are weak against Bug, Fire, Flying, and Ice-type attacks, but any type can damage a Grass-type Pokemon, either great or small.
Grass-type Pokemon are weak against Fire, Flying, Poison, Ice, and Bug-type attacks.
You beat a grass type Pokemon by attacking it with a fire type move/fire type Pokemon. I suggest numel or torkoal since those are the easiest fire type Pokemon to find. You can find them at the Fiery Path at route 112.
What works best on a grass type is fire, ice, flying, poison, or bug.
with fire type and flying type pokemon. work best for beating grass type .
Fire type has the very strongest advantage over Grass type Pokemon
Grass type
Grass type Pokemon are weak against Ice, Fire, Poison, Bug and Flying.
GRASS
You need a grass type, a fire type, a water type, an ice type, your legendary and a ghost or dark pokemon.
A Fire-type Pokemon can deal 2x the damage to Grass, Ice, Bug, and Steel-type Pokemon.
you need a fire type a water type a dark type a grass type and a dragon type.
Grass-type Pokemon are weak against Bug, Fire, Flying, and Ice-type attacks, but any type can damage a Grass-type Pokemon, either great or small.
Grass-type Pokemon are weak against Fire, Flying, Poison, Ice, and Bug-type attacks.