Ben is initially portrayed as a cocky, arrogant, and immature boy who tends to make jokes, even when fighting enemies. He easily gets full of himself and enjoys attention from others. This attitude can sometimes make him look obnoxious or dumb, often resulting in criticisms from
Gwen later
Kevinand a few others. It also causes several conflicts between him and
Azmuth.
These traits, however, as hinted in
The Forge of Creation, stem from Ben's attempts to hide his own fear about the situation (though he denied it and said he was actually oblivious). Even so, he's matured since the first series and although he can be goofy, he's also capable of great leadership skills and tends to get serious when the situation requires it.
Ben has been trained in hand-to-hand combat by black belt
Gwen (as shown in
Be-Knighted), Max, as well as various years fighting aliens, and received a basic Plumber training. Though he has only been trained on a weekly basis in order to minimize his reliance on the Omnitrixes/Ultimatrix, he is still proved to be quite exceptionally skilled in basic hand-to-hand combat as well armed and unarmed combat, being able to easily dodge shots from
Manny's blasters and proceed to disarm him while in human form in
Above and Beyond.
Ben was able to hold his own against Pierce, and Max hinted that Ben was a highly skilled fighter, even as a human in
Voided, expressing surprise about the fact he lost to
Pierce (though it is then revealed that Ben had lost on purpose). Another hint of his exceptional hand-to-hand skill is when he succeeded in the
Plumbers' Academy with a 95 out of a 100 (without using the Ultimatrix). He is also shown to be a crafty fighter. However, according to Matt Wayne, Ben isn't a trained fighter and that he uses freestyle fighting.