The Pokemon 123 in leaf green is scyther, i think you can get it by trading it from fire red...
go around mt. pyre from route 121 when you get to the other side your on route 123
123
123
Pokemon number 123 is Scyther. Scyther is a bug and flying type Pokemon with swarm and technician abilities that evolves into Scizor.
Attack of the Show - 2005 1-123 was released on: USA: 6 July 2005
Let's Make a Deal - 2009 3-123 was released on: USA: 20 March 2012
The Tyra Banks Show - 2005 4-123 was released on: USA: 31 March 2009
The Colbert Report - 2005 Charlie Savage 3-123 was released on: USA: 1 October 2007
The Colbert Report - 2005 Ross Douthat 6-123 was released on: USA: 28 September 2010
The Daily Habit - 2005 Devun Walsh 4-123 was released on: USA: 24 December 2008
The Colbert Report - 2005 Sheryl WuDunn 5-123 was released on: USA: 28 September 2009
The Colbert Report - 2005 David Karp 9-123 was released on: USA: 16 July 2013
The Daily Habit - 2005 Darrell Stanton 1-123 was released on: USA: 22 March 2006
Nanalan' - 2003 123 Apple Tree was released on: USA: 3 May 2005
Jimmy Kimmel Live - 2003 4-123 was released on: USA: 17 October 2005
The Tony Danza Show - 2004 1-123 was released on: USA: 30 March 2005