Chase was a black berkshire dumbo with a head spot.
Chase arrived with Mortemain. See Mortemain's page for their story.
Chase was also affected by the chronic abscesses that plagued these two boys, although to a lesser extent than his brother. He healed faster, and didn't have any of the other issues such as losing bits of his tail or toes.
Chase was able to be moved out of quarantine a lot sooner than Mortemain, and went into the main group. Here, he took on a fairly high position in the group, and even had the alpha role for a while.
He still suffered from the occasional abscess, and any nip he got took longer to heal than it would on any 'normal' rat. But he ultimately ended up living a fairly normal ratty life.
Chase had a stroke in his later months, but recovered well, and quickly, and had no more problems with this. But it did mark the beginning of him slowing down and becoming 'old'. He eventually died of old age, but he did very well considering his earlier life.
Why Chase? After Costas Mandylor's character in the movie 'Primal Doubt'.