>>46850535Grass, surprisingly. Gets rid of Fire's Ground and Water weaknesses, and Fire gets rid of its weakness to Ice, Fire, and Bug. Fire/Grass is only weak to Poison, Flying, and Rock, while resisting Grass x4 and Electric, Steel, and Fairy x2
Electric is another great pairing. It becomes 4x weak to Ground, but adds Flying, Electric, and Steel resists, giving Fire/Electric 7 2x resists and 1 4x resist.
Finally, I think that Ground is the best combination between defense and offense for Fire. Fire gets rid of Ground's Ice and Grass weaknesses, and Ground gets rid of Fire's Rock resist, meaning it's 4x weak to Water and 2x weak to Ground, while also resisting Poison, Fairy, Steel, Fire, and Bug, and being immune to Electric. Offensively, though, Ground hits Rock and Fire for SE, and hits Water, and Dragon for neutral, and Fire hits Grass and Bug for SE and Flying for neutral.
