Cosmo Neos Lock

Probably the most consistent Neos build I've ever made. It is ideally a going first deck, with little to no interaction (as HEROs tend to run), but it does have some workarounds and can hit pretty hard.

1: Opening move should find a way to get out Stratos and Blazeman (A Hero Lives, etc.), then use Blazeman to search Poly. Bonus if you also have access to Liquid.

2: Fuse Blazeman with Stratos (or Liquid if you have him) into Sunrise, search for Miracle.

3: Miracle Fuse the same two HEROs for Infernal Rage, search Favorite Contact.

4: Link Infernal with Sunrise (or Stratos if he's still around) into Infernal Devicer, revealing Nebula or Storm Neos and searching the two Neo Spacians.

The rest of the turn depends on what you have available. Use cards like E-call, Deployment, EN Shuffle, and Neos Fusion to get access to Neos and the third Neo Spacian. Make sure to activate Neos Fusion after already getting all your other pieces so you don't lock yourself out of summoning. Brave Neos is the ideal target. Also, save Engage Neo Space for when you have ways to get out 3 Neo Spacians without using Devicer.

End your turn by setting Favorite Contact, then activate it during your opponent's Standby Phase. They will still be able to summon and set, but will be locked out of Spells/Traps/Monster effects for the entire turn.

Nebula Neos and Neos Kluger/Wiseman can act as backups if you can't get out Cosmo, or as big game finishers even if you do.