Imu needed to:
- gigantify himself to match Loki's attack power
- counter or block every attack with massive scaled Omen attacks
- directly stabbed Loki with Nemesis, Loki still immediately continued the fight
- a single distraction caused 67m Imu to crash into the adam tree
- to that point, everything was about base Loki vs Imu (imagine if base Kaido demonstrated all these feats)
- Imu needed a massive Omen barrier to block Thorheim
- Imu vs Dragon Loki caused a massive match between nukes which were seen throughout the COUNTRY
- Imu simply couldn't destroy Ragnir's ice, acknowledged that Ragnir finally found his new master (Harald stated the struggles to tame Ragnir and thought that he's able to do this feat now with his new power)
- The battle was off panelled for Gunko's flashback, then we saw how Loki was ultimately brought down by another nasty sword stab of this calibre:
I don't know what Luffy will do now but he'll definitely need first aid as well. The issue, Luffy was facing Imu at a state which was even
beyond his peak, yet he got wasted significantly harder than even base Loki. There isn't much Luffy still can do, unless he gets a massive new PU.