Agony Crown
Every 24s, creates a wall of fire that deals 600dmg every 0.4s and burn enemies.
Note: Good AOE and very high damage to anything you can get to stand in the fire. Not mobile since you have to stay around it once it is activated to take advantage of the damage. Can be good with bosses if you can get them to move into the fire
Ingredients:
Corruption Robe
Flame Crown

Antichrist Blood
Every 5s thows a vial of antichrist blood. The vial create area that deals 50dmg over time.
Note:
Ingredients: Damage to low. Decent AOE.
Sacred Water
HellFire Staff

Blizzard Wand
Creates an icy rain every 8s, that deals 150 dmg and applies chill.
Note: Large area of random hit ice rain.
Ingredients:
Glacial Staff
Frost Staff

Darkness Cloak
Every 14s summons 2 darkness spirits around you, for 12s. Each spirit deals 50dmg
Note: It a orbiting spell that is better than Raziel's Tomb in terms of damage and distance from body. But not good for high level map. Most high level enemies can go pass the orbit weapon without getting hit and likely have high enough hp to survive several hits. If you want something that kills stuff in a small area around you, go with Underworld Tome. You can keep this up constantly with a little bit of cooldown reduction
Ingredients:
Corruption Robe
Corruption Crown

Ectoplasm Gift
Every 20s, creates a ectoplasm gift that deals 300dmg.
Note: Not a great weapon. High damage mine that detonate after a delay.
Ingredients:
Ectoplasm Wand
Explosive Gift

Frost Dagger
Every 12s, throws frost daggers that pierces thorugh enemies, dealing 30 damage. Applies chill.
Note: Necrotic Orb is a better version of this in terms of damage and AOE. Combine the two for a quicker screen clear in lower level map. The chill if really nice to have but I'm not a fan of the low damage
Ingredients:
Knife
Frost Scythe

Glacial Sword
Every 10s, creates a glacial sword that deals 500 dmg every 0.15 seconds and chill enemies.
Note: This actually rain a bunch of Glacial Swords onto a small area. Good damage and chill. But the area too small for a good clear. And not effective against fast enemies
Ingredients:
Knife
Frost Sword

Horizon Sword
Creates a horizon slash every 7s that bounces through up to 24 enemies, dealing 110 dmg.
Note: 24 enemies aren't that great. This game reward things that pass through infinite amount of enemies. The damage is decent. This is the better version of Water Staff in terms of damage and the amount of enemies it hit.
Ingredients:
Celestial Sword
Ivy Staff

Necrotic Orb
Shoots necrotic orbs every 12s, dealing 200 dmg.
Note: This is the better version of Frost Dagger in terms of damage and AOE. But it does not applies chill. Use both Frost Dagger and Necrotic Orb for a easy screen clear for early maps
Ingredients:
Corruption Orb
Slime Staff

Obsidian Scythe
Every 14s, creates a blast of obsidian scythes that pierces through enemies, dealing 300 dmg.
Note: Best Fusion Weapon in the game. Sends out scythes similar to the final boss. At max level, it send out more scythes than the final boss. Deals great damage and have the potential to clear most of the screen. The pattern is a bit unpredictable. But that is fine at max level since there are a lot of it
Ingredients:
Frost Scythe
Fire Scythe

Raziel's Tome
Every 10s, summons the Raziel's Tome to orbit your body for 7s, dealing 5 dmg.
Note: Weak version of Darkness Cloak in terms of damage and range. It does have more projectile orbiting you so enemies are likely to get hit by it before touching you. But most enemies can take multiple hits from this. You can keep this up constantly with when there is a decent amount of cooldown reduction.
Ingredients:
Thunder Staff
Holy Bible

Snow Cannon
Every 14s, shoots a snow cannon shot dealing 2000dmg.
Note: You can aim this shot. Highest damage fusion weapon in the game. great for boss fights but it is risky to build. The ingredients have no other combination and it not great at clearing enemies.
Ingredients:
Snow Gun
Silver Gun

Underworld Tome
Every 10s, creates a blast of hellfire that deals 500dmg and burn enemies.
Note: Better than orbiting weapons. Deals much higher damage around your character. Can be hard to hit high mobility enemies
Ingredients:
Hellfire Staff
Holy Bible

Water Staff
Creates a water energy every 7s that bounces through up to 20 enemies, dealing 50dmg
Note: Weaker version of Horizon Sword in terms of damage and enemies hit per cast. But it is very easy to build
Ingredients:
Frost Staff
Fire Staff