MegaMan: NT Warrior (2002)

None.

While there is plenty of animated sci-fi violence, there is never any blood, as the violence is centered on non-organic cybernetic characters called "Net-Navis". Even Navis who are "killed", or deleted, can just be brought back via back-up data, or evolve into a new program, so death isn't really permanent.

The worst you'll hear in the English dub are words like "darn" and "heck".

If you watch fan-subs, however, stronger words (da**, what the he**, and even sh**) will be used.