which team are you talking about?
The Denver Broncos Football Team.
Thunder (mascot)
Thunder is the stage name for the horse who is the official live animal mascot for the Denver Broncos football team. 
what is thunder (mascot)? A horse that is also an official live animal mascot. what is its duties as the last? The duties include leading the team onto the field at the start of every home game, and a gallop down the length of the field whenever the team scores a touchdown or field goal.
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Thunder (mascot) [SEP] Introduction
Thunder is the stage name for the horse who is the official live animal mascot for the Denver Broncos football team. Three purebred Arabians have held this role since 1993, all gray horses whose coats lightened with age until they turned completely white. Sharon Magness-Blake has owned all three horses, and Ann Judge has been their rider since 1998 and trainer since 1999. , Thunder has appeared in four Super Bowls with the team since 1998. The original Thunder performed in Super Bowl XXXII and Super Bowl XXXIII and Thunder III appeared in Super Bowl XLVIII and Super Bowl 50.