Once a regular fox, Oak Lord's favorite object was a chainsaw. Not for killing people though. For cutting down trees. But then, one day, he was payed for his actions and, somehow, got turned into a tree himself.
A year later, Oak Lord was bought to life by a strange wave of energy. He then built an entire city with it's residents being living trees and was bought up as it's mayor.
Plot to the storie
In Sonic: Alone Z, Oak Lord guides Sonic through Oak Town and it's resident's way of life. Near the end of the Oak Town arc, Oak Lord is about to tell Sonic more about their village until Eggman comes and hypnotizes Oak Lord. Oak Lord then turns into a shadow monster hybrid and tries to kill Sonic. Sonic, like always, wins and Oak Lord gets reverted back to his normal self.