Board Thread:Fun and Games/@comment-29800728-20161128144239/@comment-24020008-20161207160304

Epsilon had the memories of Alpha (before Alpha fragmented Epsilon, so he didn't receive memories such as Blood Gulch) and the Director from the start. When Epsilon and Alpha made contact with each other in Season 6, a small amount of their memories were exchanged, but not that many. As Caboose was working on building a body for Epsilon in Season 7, he was telling Epsilon stories of Blood Gulch and their adventures. So when Epsilon finally gained a body (the monitor), he had a somewhat messed up memory of the BGC, getting some parts of their past wrong.

He appeared as Delta for a brief amount of time because the memory exchange with Alpha gave him the information about Delta (some of it) and Caboose told him about Delta. After this, he more or less fixed his memories with information that he gathered from the other members of the BGC, so it wasn't the incorrect Caboose version.

When he entered the storage unit to go after Tex, however, the incorrect memories took priority, and Epsilon had to try and fix the memories to get Tex to show up.

After Epsilon was retrieved from the storage unit, his next source of information was CT's dog tags/flash drive thing, where he was able to put two and two together and "remember everything", including the other AI fragments entirely.

So that's why Epsilon can remember stuff. I would answer the other questions, but my comment is getting extremely long, and Hodgepig could probably answer them.