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X1: Boring
X2: Great
X3: Terrible
XMO:W: Amusingly bad, so good.
The Wolverine: Awful
FC: Mostly Great
DOFP: Bad

Not seen Apocalypse. Possibly thankfully.

The trailer doesn't have to be linear though.
The burial scene could be a flashback.

Yeah, and that fits with Old Man Logan.

My guess is that Xavier is just in his head, and doesn't actually exist anymore.