Megas XLR - Season 2 Episode 5 -

Once again, Coop mistakenly releases a giant, plant-type alien menace that wants to destroy Earth and acquire its heat. Fortunately, Megas is too big for the plant to handle, so it has to find a bigger form. Unfortunately, this is Thanksgiving, and the spore fuses with a bunch of parade balloons to this end. Coop now must prevent the plant from wrecking the holiday.