Performed in sunny weather against a Heatran with Bug Bite + Iron Head. This was probably the single Heatran moveset that I most wanted to see, although I think a charged move of Flamethrower or Fire Blast would've been fine too.
Groudon is level 45. That is high enough to reach the final Mud Shot breakpoint in this raid. Compared to a level 51 Groudon, I seem to have missed out on 350 total charged move damage, assuming that my math and counting are correct. So the drop from level 51 to level 45 isn't quite trivial. An extra 350 damage might've actually made for a more comfortable ending in which I didn't need to bring out Garchomp for a hasty Earth Power finisher. But between my existing Groudon XL candy, my stash of rare XLs, and a lot of walking, level 45 was the best I could do for now. Thankfully, it was enough.