Wilson is Paul's companion in Man vs Minecraft. He was befriended by Paul in MVM S2E1, but was finally named Wilson in episode 2 of the same season, a refrence to the movie Castaway.
Wilson has been Paul's companion since Season 2, and was always their for him, except for the majority of season 3 and 5. Wilson was replaced in the making of season 2 finale. Paul loaded up a new map using a custom seed, and had to find a new dog to play the part of Wilson.