If my Fire type pokemon, uses a fire type attack, while holding Charcoal (fire type attack booster), will the pokemon type & held item bonuses stack up?
Blaze, Charcoal, STAB, super effective, everything you can think of stacks.
But .. seriously .. don't use those item-boost things like Charcoal and Miracle Seed. Just put Leftovers on if you can't think of something to put on one of your dudes.
Hmmm so many anti-attack boosters, well, I'm believing you all. My Vaporeon holds leftovers so I suppose saving up for a brightpowder will be my next main goal.