really great team dude, it's pretty solid. like you said, jellicent is a giant threat because you can't really do much to it while it can poison a lot of your pokemon while you can't really attempt to status it back because you'd lose a key team member. something to consider could be running a different pokemon over jirachi. heatran looks very promising in this spot, as it allows you to check sun teams that are problematic, and you can additionally tank outrage, draco meteor, hurricane, and more even better. while it isn't apparent, you also have a better way to mess with jellicent, as it fails to 3HKO you (if my memory doesn't fail me). a simple set with 248 HP / 252 SpD / 8 Spe with a calm nature and a moveset of lava plume, earth power, toxic, and roar should suit you well. this allows you to check nasty plot celebi if it doesn't carry earth power, though admittedly they usually do. however, you get a much better check to volcarona, and you are better able to handle sun teams that looked problematic. with a weather control core of gastrodon, skarmory, and heatran, you basically have most sweepers covered as best as possible. i really don't have much else to say man. cool team and good luck; i hope i helped!
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