If you have played Vampire Survivor-likes before, then you would know that certain combinations of weapons allow evolution. This game is no different. Once you get a certain combination of curios max level then receive a chest, you will get an evolved curio. This guide will tell you what curios you need to unlock certain evolved curios.

(This guide is a work in progress that will be updated as I find them. If anyone else finds some, feel free to let me know.)

Midnight Threat = Doom Scroll + Portable Galaxy
Device Activation and Device Tick summons meteors from the sky.

Recursive Scissors = Suspicious Mirror + Crit Suitcase
Bullets ricochet when they crit. (Will ricochet again if they crit again)

Melted Light = Lightning Bottle + Teapot
Fast Reloading lightning causes secondary explosion

Death Do Us Part = Teddy Bear + Gamblers Coins
Damage area now chance to heal and knockback. Temporary boost for each enemy it kills.

Chain Light = Deffered Frustration + Refreshing Brew
Whenever you use Impulse Gear and shock enemies, apply the static debuff. Shooting enemies with static has a chance to shock all enemies that share the debuff. (Contributed by Feit-Neo)

(These are just the ones I have found, will update as I find more. If you find any, feel free to let me know.)