Short Guide on How to Unlock the Secret Character Cosmo Pavone in Vampire Survivors.
To unlock Cosmo, you will first require the Yellow Sign relic. If you haven't got it already, check out our guide on How To Unlock Yellow Sign. The second requirement is that you have the character Zi'Assunta Belpaese unlocked. If you haven't done so already, you can unlock her by opening her coffin in the Cappella Magna stage or by using the cheat code 'paradigmshift' if you have unlocked The Forbidden Scrolls of Morbane.
To unlock Cosmo, simply enter the Cappella Magna stage with a character that has 0 Golden Eggs.
Note: Toggling Golden Eggs off will not count as having 0 of them.
Once inside the stage, level up and collect the Peachone and Ebony Wings weapons.
After doing so, open your map and you will see the Crown and Tirajisú passive items in the northern part of the stage. Walk a bit north beyond those two items, and you will find a balcony with a Nduja Fritta Tanto pickup in front of it. Collect it, and the gate to the balcony will open, allowing you to collect Cosmo Pavone, who is just standing there at the edge of the balcony, thereby successfully unlocking him.
If you prefer, you can unlock Cosmo using a cheat code. Simply access the Secrets menu, which you can find in the main menu if you've unlocked The Forbidden Scrolls Of Morbane. Then, enter the code 'lhovistoio' and you will have Cosmo unlocked.