Maybe it speaks to the nostalgic Horde members more than the rest of us, but I think the Interactive Horde Onyxia Attunement Chain is probably Wowcrendor's best work yet. It has the same subtle sense of humor shown in his previous work, but then takes it up a notch by speaking to one of the single most prominent, painful moments in any Horde member's life.
Like so much of Wowcrendor's work, it's not only the in-game references that make his work relay so much truth. It's also the subtle nod to universal experiences. (For example, my favorite part is when you choose to not do the quest. If you go down that path, your guild leader yells at you to get your act together. C'mon, haven't we all been there at one point or another?)
As a note, make sure you do not simply play this video. The experience is best if you visit Wowcrendor's start page for this adventure.