Today I slew a troll.
The act isn't unusual for me, seeing as I'm a troll-whisperer by profession. Sometimes trolls just get cranky and start chucking boulders around, usually at me...
Trolls are also very thick-skulled creatures (in more ways than one) and sometimes just don't want to be whispered to.
This creates a very uncomfortable situation that endangers not only me, but the troll's owner(s) and anyone else lurking around. I don't get paid unless I perform a thorough troll-whispering and death is a pretty good obstacle to that. When that happens the owner demands I pay for the slain troll, then I yell and scream about safety and how I'm not an obedience trainer and how that hat shouldn't ever be worn in public and how their face is what sundered Beleriand and not the Valar kicking Morgoth's ass. Then I get slapped with lawsuits.

So in the interest of not having my pointy ears sued off I've drawn up a waiver absolving me of any liability should the troll get unruly and merit a slaying. Same goes for the owner. I wonder why I didn't think of that before...