King's Knight happened in 1986.
It's called a stalemate when the only pieces left on the board make it impossible for a checkmate to occur. This can happen when there are only two kings left, but it can also happen when there are two kings and one knight, or two kings and one bishop, and a handful of other cases.
Arcana Knight Joker Sources: http://yugioh.wikia.com/wiki/Arcana_Knight_Joker
Cyber Knight happened in 1990.
Knight Move happened in 1990.
Knight Force happened in 1989.
Knight Lore happened in 1984.
Clockwork Knight happened in 1994.
Knight Tyme happened in 1986.
Future Knight happened in 1986.
Cute Knight happened in 2005.
Tecmo Knight happened in 1989.
Rocket Knight happened in 360.