Other World was a weird bendy/action figure toyline with heroes, villains and steeds that also boasted glow-in-the-dark weapons and accessories. The GITD weapons were the bomb-diggity and really set the Other World toyline apart from other toys of the time.
This guy is Lava-Man (or is it Lava Man, or perhaps Morty Lavaman of the Long Island Lavamans?) And...yeah, that's all that I or probably anyone knows about Lava-Man.
Sadly I didn't hold on to my childhood Other Worlders (oh Froggacuda, I hardly knew ye). The only other Other World toy I currently own is Gaifand who, like Lava-Man, I found at the flea market. These things just don't pop up much at all on my toy hunts.
I'm pretty sure the first draft of Heart's hit was originally titled Froggacuda but Nancy Wilson knew your feeble minds just couldn't take it. So Anne suggested 'Barracuda' instead and the rest is rock and roll history.