What do you think was the HARDEST hurdle for you, in SL1?

This is more a discussion, because I think the amount of uniqueness encounters in this game can have per player is beautiful. What's a moment you remember fondly because of how intense a hurdle it was? Also bonus if it's your favourite moment from a run.

Me, personally, I've got something I don't see many way - Radagon + Elden beast at RL1 is the hardest experience I've EVER had rl1. Malenia, Radahn, the usual suspects were hard, but fair. Radabeast, though, GOOOOD. It took me MONTHS. SEVERAL MONTHS. Had to resort to a blackflame AoW pike and balls. God, it was soul crushing, but the moment I beat it was unreal.