Once in a blue moon, the retro RPG community stops what it's doing, looks at each other, and says, "So we're all in agreement, right? We all notice Frog from Chrono Trigger has Earthworm Jim's bicep? And we all think that's kind of weird?"
Redditor "mr_plopsy" brought up the question again in the Retro Games subreddit. "Did anyone else wonder why Frog had Earthworm Jim's arm," they ask. Some redditors respond "Yes." Others have questions like, "Why did Frog speak in Elizabethan English?" to which redditor "elegnaim" astutely responds, "Well, have you ever encountered a frog speaking non-Elizabethan English?"
If you're not aware, Frog flexes for his Chrono Trigger victory pose, and his biceps do indeed bulge to a cartoonishly large size. Inflated, they look very similar to Earthworm Jim's 24-inch pythons. Earthworm Jim became a runaway video game hero around the same time Chrono Trigger hit the SNES (1995), which made it impossible for some people (e.g. me) to ignore the similarities between a ripped earthworm and a jacked amphibian.
Said similarities are just a weird coincidence, though. If you zoom in close to Frog's flexed arm and compare it to Jim's (check The Spriter's Resource for clean Earthworm Jim sprites), you notice small but important differences between the pixels. It just so happens Earthworm Jim's suit is white, Frog's arm is likewise pale, and they both wear blue gloves ringed with golden bracers.
No offense to Earthworm Jim, but Chrono Trigger doesn't need to steal resources from it, or other games. It's an epic quest born of unparalleled talent. That's why we chose Chrono Trigger as our #1 RPG of all time.