Outdated...

Last Update: 14.03.2022 - v0.3.1c - EA

New:
song of mana Song of Mana + Skull O’Maniac = Mannajja

Pentagram + Crown = Gorgeous Moon

 

whip Whip + Hollow Heart = Bloody Tear

Magic Wand + Empty Tome = Holy Wand

Knife + Bracer = Thousand Edge

axe Axe + Candelabra = Death Spiral

cross Cross + Clover = Heaven Sword

King Bible + Spellbinder = Unholy Vespers

Fire Wand + Spinach = Hellfire

Garlic + Pummarola = Soul Eater

Santa Water + Attractorb = La Borra

Lightning Ring + Duplicator = Thunder Loop

Peachone + Ebony Wings = Vandalier

 

Source1: https://gamerjournalist.com/vampires-survivors-weapons-and-combinations/
Source2: https://www.mejoress.com/en/how-to-evolve-song-of-mana-in-vampire-survivors/
Source3: https://primagames.com/tips/vampire-survivors-new-achievements-guide-version-0-3-0-march-2022