Rogerhunter said:
Does anybody understand what is going on anymore? I thought the earl is mana
The Earl is an entity trying to possess Mana in this flashback, he once did and it's trying again, and as of the present time (when most of D.Gray-Man is unfold) we know he succeeded. What is interesting now is to know how, when both Cross and Apocryphos (this dumbass probably doing the contrary) are targeting it.
Another thing you need to know is that the Millenium Earl is Adam, and like other Noahs, it acts like an extreme personnality disorder. You can see it as Venom, but it's both physical/material (or that's only due to its reaction to Allen's Innocence and they can't be separated otherway) and mental/non-material, and as for Allen with the 14th, Mana has crysis periods where the Earl manifests itself/take over. He seems to be conscious of it and he's struggling against the Earl's spirit.
Can't reveal you all of D.Gray-Man's mysteries, it gets solved little by little. That's how you need to process it, it takes a little bit of imagination and thinking. 'Ok I've got this info, it happened like that, so what can I take from it and what can I exclude?'
Allen's memories having been alterned too, PROBABLY, if you only rely on the manga's (Allen's) beginning knowledge, it probably won't be enough to understand what is happening.
(I mean that's the whole purpose of this flashback... Other manga don't necessary go that deep, for this amount of time irl, but DGM does because it can't be done otherwise.)