In my current game, I don't get the energy blast from the Bloodskal Blade, which means I can't continue that quest. I've never had this issue before. Checking with TES5Edit, the only mod I have that directly affects it is the Unofficial Dragonborn Patch, but the issue isn't caused by it. Anyone who has an idea what might cause the issue?

Why do you say that the unofficial patch is not the responsible if it's the only mod that affects the blade? I'm not using them and this blade has always worked perfectly.

Because if I load the save without the Unofficial Dragonborn Patch, it still doesn't work.

EDIT: I got around the issue by temporarily using http://www.nexusmods.com/skyrim/mods/32237/?, but even with that the effect was glitchy and only worked sometimes. No idea why. I never use the sword after the quest so I can live with the issue, but it's quite odd so it would be nice to track down the cause.

EDIT: Also, the blade works as it should after leaving the barrow so I guess it was some kind of annoying glitch.