I was trying to clear a path between an Invulnerability Globe and the stairs, so that I would max out my invulnerable time. It was at about level 20, so it would have helped in case the game decided to spawn multiple Arch-Viles next to a group of Revenants. This very thing had happened twice to me already, one of those on my current level. I had very low health, below 15% I believe, and was planning to grab the Invulnerability Globe rather than waste one of my precious Large Med-Packs. I was moving some barrels next to walls to blow a path through, as I lacked a Rocket Launcher. I normally use either a pistol build, with Son of a Gun, Eagle Eye, and Dualgunner, or a chaingun build with Son of a Bitch, Eagle Eye, and Triggerhappy, so I don't normally keep the Rocket Launcher after I used it to blow my way through The Wall. I was not paying much attention at the moment, as I was thinking about how I was to reposition the next barrel I needed to use, and pushed my current one right into some lava. So because of my extreme stinginess with Invulnerability Globes (am I alone in this, or does anyone else treat them similarly?) I inadvertently caused the death of my character.