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One commentI like this addon, Boss Notes. Gives you an in-game notebook for each boss.
Comes with dot-point reminders of the key things for Ulduar bosses, for example, and you can enter your own. These can be broadcast to a channel you choose.
Another example of what a warlock might put in a personal note for a boss:
It also knows and learns the abilities that boss’ cast, so you build up a reference database of their spells, which are tooltips and linkable. I particularly like this feature, since sometimes this is all you need to check.
The addon Boss Notes has been under continual improvement for a while now, is regularly maintained, so appears to be a safe choice to rely on for your raid leadership notes.
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It kinda reminds me of an addon I used in late BC.
Can’t remember the name, but it “captured” bosses’ abilities (and maybe trash’s as well) which were then linkable from the addon itself.
The abilities were listed by instances and then bosses.
It prolly doesn’t work (or is discontinued) anymore.