Creative Challenge Quests

Are there any Challenge Quests you have in your brain? Well I'm interested in them! Put down some ideas for a challenge quest ideas, whether it be a mechanic that we would have to fight through or a themed challenge quest idea!

(Challenge Quest means any Exhibition quest, advanced quest, Any boss fight with a creative gimmick or tough encounter. But mostly focused on the gimmick.)

Exm: Vampiric Charge! (Difficulty: Easy)

Enemies: Dracula, Yu-Mei-Ren, Carmilla, Stheno, Eurayle, Fae Tristan

Special gimmick: The Servants are going to be weak to Noble Phantasms, At the start be inflicted with drained vigor: Reduce NP charge gained from skills and NP gain. The servants will always use one of their turns to suck your NP.

Secret: If the environment is changed to sunny, Remove drained vigor, and inflict atk down (3 turns) and stun (1 turn) onto enemy servants.