The general reaction from the fandom in Retrace LI when it's revealed that Reim is the contractor of the chain 'March Hare'. Mochizuki was not exactly subtle in hinting this.
Retrace LVI, in which Reim is revealed to be alive and kickin'. Turns out that March Hare's power is faking death. Guaranteed, this theory showed up at least once in every PH forum on the Web. For the most part, the fandom was pleasantly surprised that they were right.
Retrace LXIX, which confirms the assumption that Alice and the Intention of the Abyss are the children of Lacie.