Board Thread:Spoilers!/@comment-413929-20151029063935/@comment-3010035-20160222003629

 Fitting for the milestone episode, a character whom we first met in the series pilot and who has not been seen in a while resurfaces when you last expect — to great comedic effect.

Potential answers are Ryan, tha Jailer, and the Bishop.

(Even though the Bishop was last seen in Operation Mongoose Part II, and the Jailer in the Season Five Promo)

The wolf from Pilot, that was also featured in Lily is another option...