019 Nick

Nick is the ninja.

A ninja is a covert spy or mercenary, with historic precedence going back to 15th century Japan.  While a samurai fought openly and with honor, the covert nature of a ninja was seen as a dishonorable means of warfare at the time. However, they were definitely used to stealthily spy upon or attack an enemy. Ninjas were also used for sabotage, arson, and assassination. 

The ninja as a stock character in popular culture goes back to the 1960s and the James Bond franchise.  They became especially popular in the 1980s as characters in toys and cartoons such as G.I. Joe and Teenage Mutant Ninja Turtles.

The G1 Nick wears a gappa (travel cape) and kusari (hood).  Although ninjas historically just dressed as civilians, it has become popular in media to depict them in black attire.  In addition to his "regular" black version, G1 Nick can be found in white, red, blue, and green.

Interestingly, these are the exact 5 colors of the ninjas in the toyline and TV show LEGO Ninjago.  This property also features a sensei, a samurai, a female warrior, dragons, and skeleton people.

These TDD were all out by 2002.  Ninjago wasn't created until 2011. Tech Deck did it first.  (Just sayin'.)

Nick's G2/G3 version has a fighting stance and a sword in his right hand.  The G2/G3 figure is a completely unique sculpt compared to both G1 and G4.

Nick is only one of two existing characters to get a brand new G4 sculpt (not counting Trick Dudes) and the other is Woody.  The re-sculpted G4 Nick was made with white and black versions only.   This seems to reflect the epic conflict between the characters Storm Shadow (white) and Snake Eyes (black), the popular ninjas from the G.I. Joe series of toys, comic books, cartoons, and movies.  The TDD figures have katanas (swords), also similar to the depiction of these famous characters. The relevance of the redesign certainly relates to the first G.I. Joe movie which came out the same year (2009) as these versions of Nick.