Sometimes the world needs heroes. And sometimes they are found in unlikely places. In 1999, a creature from another dimension attacked us. Earth's heroes fought back, but were destroyed. Several of their arch-nemeses sensed that it was in their best interest to protect Earth against this new enemy. Even though they acted purely out of self interest, they became the heroes that Earth needed. They defeated that other-dimensional monstrosity and in the process they got a taste of what it's like to be good. Now these heroes, who were once relegated to console games of the 1980s and 1990s, protect the world and avenge any wrongs against humanity.
Bowser as an Avenger
Ganondorf as an Avenger
Dr. Robotnik as an Avenger
Sephiroth as an Avenger
And, just for fun, here are a few images that didn't match the prompts in the way that I wanted but that I still thought were worth keeping.
These illustrations were drawn using Stable Diffusion 2.1.
