Kai

 Kai is a red ninja minifigure released in 2011. His father was the blacksmith that Sensei Wu gave the map to the golden weapons to. Kai is the Ninja of Fire. Nya is his sister.  He is was the last to reach his full potential. Kai has been known to have a bad temper.

Variants

LEGO Ninjago: Masters of Spinjitzu

Other

Name:  Kai
Variations:  Normal, DX, Kendo, Microfigure, ZX, NRG, Kimono, 2014 Variant
Years:  2011, 2012, 2013, 2014
Color: Red
Element: Fire

Appearances:
2111 Kai 
2505 Garmadon's Dark Fortress 
2507 Fire Temple 
2508 Blacksmith Shop 
2518 Nuckal's ATV 
2254 Mountain Shrine 
2258 Ninja Ambush 
3856 Ninjago 
9558 Training Set 
9441 Kai’s Blade Cycle 
9443 Rattle Copter 
9449 Ultra Sonic Raider 
9456 Snake Battle 
9561 Kai ZX 
9591 Battle Pack 
30083 Dragon Fight 
70500 Kai's Fire Robot
70721 Kai Fighter
853097 Kai Key Chain 
Kai Alarm Clock
LEGO Battles: Ninjago
LEGO Ninjago: Masters of Spinjitzu