Thought of doing a Nuzlocke of Photonic Sun but wiping multiple times Totem Lurantis, I went with "gift only" run with set mode, no items from bag and level caps for Kahuna + Totem.
While EV training is easy, it's not possible to change nature or IVs. Boss battles have Smogon sets having access to moves that you don't have till the end of the game. Totems are overhauled to have +3 omni boosts later in the game. Ultra Necrozma can SOS call Naganadel, is level 100 with +3 on all stats.
On this challenge, at certain point in the game, I was frustrated because of type coverage. Imagine running a team that is weak to Electric, Steel, Fighting and Ground.
I had high hopes with Rock Head A-Marowak but lining it up for kills didn't work. Same with Naganadel. Bastiodon was fun to use especially with Totems. Sturdy + Metal Burst had more kills than others. Scarfed Aurorus with Refrigerate was good as well but didn't do well against resistances.
People have Nuzlocked this game in hardcore mode. One even did 1 death == reset but I have no energy to do so. Maybe in future.