Operation: Puffle is a special mission in the series of In-Game Missions and party in Club Penguin to occur in November 2013.  It will involve a big mystery in Club Penguin. It will expand Club Penguin, and is something that the audience has been asking for a long time.  It will also involve being lost in the wilderness.  It will be related to puffles, as seen in the Halloween Party 2013 trailer and on the Club Herbert website.
This is also possible because Herbert was seen in the Halloween Party 2012 trailer, and he was the main reason for the following party as he did in Operation: Blackout. It could be a direct sequel to Operation: Blackout because they both star Herbert as the main antagonist.
On October 8, 2013, Polo Field hinted in the Wikia Chat that the mission may involve puffles, and a possible name was revealed (Operation: Puffle).
Spike Hike on Twitter has confirmed that the name of the EPF Mission is Operation: Puffle.
The mysterious secret ingredient, the Golden Puffle O, from the Medieval Party 2013, may make an appearance, and the Golden Puffle, as well. It was mentioned in a What's New Blog post. PH and Gary are currently studying it, who coincidentally, are both part of the Elite Penguin Force.