Power Stone, fond memories right there. I didn't even know there was a Spawn game on Dreamcast; the only Spawn game I knew of was Armageddon on the OG Xbox
The Dreamcast Spawn game is kinda like Power Stone (it's also by Capcom, so there's that), in that it's a small battlefield and the characters can all duke it out, only there are guns, grenades, knives, swords and blood (also offense/defense/health power ups). The control is rather clunky, as you move with the d-pad instead of the analog stick. Totally worth checking out