To be honest, Animorphs always struck me as less viable for RPGs than a really good tabletop squad-tactics wargame, what with prebuilt characters and the sheer variety of tactics the kids employed over the course of the story. Thought about doing modules in that vein?
I know basically nothing of squad-tactics wargames, so I don't think I'm qualified to answer this one. But if anyone knows of something similar among the Animorphs games out there, then HMU with a link.











