The oddly named Sword & Sandals II makes you a gladiator that can level by dueling other gladiators. Similar to the Flash-based based Adventure Quest RPG (affiliate) only you don’t play against any other human players as best as I can tell, it’s only you against the machine.
You can play a demo version of S&SII online which will allow you to play to level 4 before stopping to say you need the full version to continue. The full version can be purchased for a one time fee of $19.95 or played as a gold member at the site Playaholics. The Flash graphics are nicely drawn with some grizzly finishing moves during duels.
It’s too bad they don’t let you keep playing this game and go more for the approach of Adventure Quest, Dungeon Runners and Runescape by offering more features and functionality for members rather than offering a short trial only.