- First up, the raid finder (LFR) will still aim for a fixed group size of 25 players. However, if you're in an LFR group and players drop before the next boss, that boss will scale to the size of the current group - as an example, if a raid of 25 players is fighting Paragons, then four players drop on the way to Garrosh, Mr. Hellscream (if you're nasty) will scale down to a 21 player size.
- What we now call the Flexible difficulty will become Normal in patch 6.0 - it will scale just as it does now.
- What we now call Normal difficulty (10 and 25 man) will scale flexibly and will be called Heroic difficulty. It will scale just as normal does.
- Finally, Ion pointed out that scaling the most challenging encounters in terms of design requires a fixed raid size, and so, they've chosen that size to be 20 players. This difficulty, analogous to what we now call Heroic will be called Mythic difficulty.
Also, please forgive me a moment of smuggery, but I called it.