Eternal

At point blank range you can’t possibly miss and fire engulfs the troll’s face. Naturally this does indeed cause it great pain, but just like the first time you hit it in the face with fire, it doesn’t slow it down for whatever reason, it just enrages it further and its vice like grip on your arm squeezes tight enough to crush the bones within. As excruciating as that pain is, its nothing compared to when troll takes its flaming head and smashes you in the face with it.

You nose is broken and your skull is fractured in several places, to say nothing about your own face now being on fire. The troll finishes ripping your broken arm off at the socket before throwing you off the platform several feet below. You can and have withstood lots of physical punishment in your life, but you can’t survive this amount of massive trauma. You die as soon as the back of your head hits the stone floor.