Colossal Red can be seen circling between Mt. Koula and Port Bludor in the map below, the location of her lair (in what is known to some as "The Painted Spires", or to others as "the old location of the citadel paints display"). Over the years Colossal Red has been much feared, and generally rightfully so. Eventually, the miniature was gifted to the resident expert DM, but the legend remained, and has made its way into the Age of Sigmar.
In the recent Game Day, Colossal Red skipped town to go hunt megafauna up in the frozen lands to the north (either that is Colossal Red is the secret Santa). Whatever her motivation may be, the various forces warring for control of Eucebium noticed her absence and moved in quickly to attempt to claim her treasure for themselves.
I set up two battlefields for this event (as I usually do), one of which represented the Rocky Ascent to Colossal Red's lair, and the other of which represented the Duardin Catacombs beneath her lair. For the Duardin Catacombs, I used some Zone Mortalis terrain that the 40k players made, and I'm not sure it was a great idea. Most of us had monsters of some vein or another, and the Zone Mortalis terrain was very constricting. So I think I shan't be doing that again.
Overall, a good time was had, and Slaanesh ended up winning and making off with the treasure. What was Lady Rheatrivix's goal for the ill-gotten gains? To make an offering to her patron in the Eye of Terror (and 41st millennium!). So next month, we'll be including 40k warscrolls as an option in the Game Day as a special one-off thing, which should be wild and crazy, but will certainly give Rheatrivix full credit for her victory.