Synth engine in Prophet X

Does anyone happen to know what synth engine is in the Sequential Prophet X? I've been looking for this but can't find it.

Someone suggested that it's the Prophet 08. But I don't see any evidence of that. Is it something that's just unique to the X?

I know the X is loaded with samples that can interact with the synth engine, but I know it also be used as just a synth, so I'm curious what that synth is based on.

Thanks.