According to Heroes Wiki, Sylar has: intuitive aptitude, telekinesis, freezing, enhanced memory, melting, enhanced hearing, precognition, induced radioactivity, rapid cellular regeneration, and alchemy.

Peter has precognative dreaming, flight, precognition, rapid cellular regeneration, telepathy, invisibility, telekensis, space-time manipulation, induced radioactivity, super strength, lightning, and phasing. On top of all that, he's acquired powers that he hasn't used yet. Count that and he's got persuasion, intuitive aptitude, freezing, enhanced memory, mental manipulation, melting, enhanced hearing, clairvoyance, technopathy, alchemy, enhanced speed, magnetism, pyrokinnesis, and sound manipulation. Along with whatever powers he acquires from the Level 5 guys too.

Conclusion - Peter > Sylar

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