>>42478723GRASS is weak to:
-FIRE
-ICE
-POISON
-FLYING
-BUG
ROCK resists:
-NORMAL
-FIRE (see above)
-POISON (see above)
-FLYING (see above)
ROCK is strong against:
-FIRE (see above)
-ICE (see above)
-FLYING (see above)
-BUG (see above)
By posing as a Grass-type, Bonsly/Sudowoodo are guaranteed to be hit with things they either resist or can take out with supereffective damage. It’s ingenious really.