Ryona

I always saw Don as second to Leo in both age and fighting skills in the original series. That boy has some mean skills.

Infact, here's the order...

Leo is the oldest and the most skilled, which is constant in all TMNT universes.

Don is the second oldest and seems to be the second skilled fighter.
Sure, he spent time building stuff (which were always very impressive machines in the original series), but he also seemed to put alot of attention and precision in his training.

Raph is the third oldest and seems to be the third skilled fighter, which kinda makes sense givin the fact that he spent alot of his time watching TV or having fun with Mikey.

Mikey is the yongest and seems to be the least skilled fighter. In the first season when Mikey was sparring with Leo and gets tossed into a wall, Don, Raph, and Splinter rag on Mikey to try to stay sharp and focused.

Interesting enough, that's the order that they're introduced in the TMNT theme song.


Though, ofcourse, compared to just about every other character to ever appear in the original series, all four of them were generally the better fighters.