Mud crashes killing Dark-elven Transmuter

So this happened a week ago, I thought maybe it was just a coincidence. But today again, exactly the same way. In between I killed it as a group (much faster) and no issue. It was when i solo it. And always on convulsing in the exact same way. wilderness subterranean <1057hp 595m 816mv 26000tnl (-24.40%) 10 AM> You dodge the dark-elven transmuter's piercing venoms. You get in one more shot on the dark-elven transmuter as he flees. Your parting blow DISMEMBERS the dark-elven transmuter! The dark-elven transmuter has fled! The dark-elven transmuter leaves east. wilderness subterranean <1057hp 595m 816mv 26000tnl (-24.40%) 10 AM> dash e under trans A Mine Shaft on the Second Level [Exits: west] (Purple Aura) (Translucent) A rogue dark-elf slinks in the shadows. You close into the dark-elven transmuter with some strong thrusts up under his ribs. Your underhand strike DISMEMBERS the dark-elven transmuter! Your underhand strike MASSACRES the dark-elven transmuter! The dark-elven transmuter is convulsing on the ground. wilderness subterranean <1057hp 595m 813mv 26000tnl (-24.40%) 10 AM> The dark-elven transmuter utters the words, 'eugfjsh yrzgp'. Your skin twists and splits under the dark-elven transmuter's magical assault! The dark-elven transmuter's disruption EVISCERATES you! You dodge the dark-elven transmuter's piercing venoms. You fail to get in one more shot as the dark-elven transmuter flees. The dark-elven transmuter has fled! The dark-elven transmuter leaves west. wilderness subterranean <1012hp 605m 840mv 26000tnl (-24.40%) 11 AM> dash w under trans A Mine Shaft on the Second Level [Exits: north east] (Purple Aura) (Translucent) A rogue dark-elf slinks in the shadows. You close into the dark-elven transmuter with some strong thrusts up under his ribs. Your underhand strike MASSACRES the dark-elven transmuter! Your underhand strike DISMEMBERS the dark-elven transmuter! The dark-elven transmuter is convulsing on the ground. Connected to host 162.249.126.23605m 837mv 26000tnl (-24.40%) 11 AM> Using shadow dagger, ghostly dagger. I believe i dash underhand each time Imperial offense haste stoneform berserk