The Shadow

From Jak and Daxter Wiki

The Shadow is first introduced by this name at Jak's first meeting with Kor. Jak learns that The Shadow is the leader of the Underground movement & a very powerful individual. It's later discovered that The Shadow is in fact a younger Samos. The young Samos is sent back in time with the Kid, who is revealed to be young Jak, to raise him so he can deal with the responsibilities that Jak is currently going through.