Is there a scripting addon that will make one easily do that?
If boss_name="Majordomo" is=killed then="/w caster_name "Don't forget to siphon it immediately""
I know you could write a whole addon for it but I wonder about any scripting ones.
Moved to Interface and Macros. Raids and Dungeons is the wrong forum for this kind of post.
I would just simply say it over vent and make an in game macro you can hit on kill. Honestly if the person going for the Legendary can't remember to siphon they probably don't deserve the Legendary.
/s Don't forget to siphon it
Though I agree with chubbs, if you can't remember something simple like that, you don't deserve a legendary.