I say yes to the forging of weapons as a viable idea, but not with already existing rare weapons, but with common weapons including Dagger, Short Sword, Hammer and Short Bow. Your only opportunity would be through the Oracle and the "Forge Key" System proposed by Thelonesun.
The combinations could be:
Piece 1 | Piece 2 | Piece 3 | Rare Weapon Produced |
Short Sword | Hammer | Short Bow | Discord |
Dagger | Dagger | Hammer | Arsenic |
Hammer | Hammer | Hammer | Titan |
Hammer | Hammer | Short Bow | Pulverizer |
Short Sword | Short Sword | Short Bow | Druidic Staff |
Short Sword | Short Sword | Hammer | Farenheit |
Dagger | Short Sword | Hammer | Trident |
Short Sword | Short Sword | Short Sword | Morning Star |
Short Bow | Short Bow | Short Bow | Owl's Eye |
Dagger | Hammer | Short Bow | Eternity |
Dagger | Dagger | Dagger | Vampire Stiletto |
Dagger | Short Sword | Short Bow | Lobotomizer |
And if you want an upgraded version, you'll have to provide at least 2 upgraded "pieces"
Actually, there are 20 possible combinations.
Dagger+Dagger+Dagger = Vampiric Stiletto
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Dagger+Dagger+Shortsword = Arsenic
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Dagger+Dagger+Hammer
Dagger+Dagger+Shortbow
Dagger+Shortsword+Shortsword = Lobotomizer
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Dagger+Hammer+Hammer
Dagger+Shortbow+Shortbow
Dagger+Hammer+Shortsword = Druidic Staff
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Dagger+Hammer+Shortbow = Eternity
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Dagger+Shortbow+Shortsword
Shortsword+Shortsword+Shortsword = Morning Star
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Shortsword+Shortsword+Hammer = Fahreneit
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Shortsword+Shortsword+Shortbow
Shortsword+Hammer+Hammer = Pulverizer
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Shortsword+ShortBow+Shortbow
Shortsword+Hammer+Shortbow = Discord
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Hammer+Hammer+Hammer = Titan
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Hammer+Hammer+Shortbow
Hammer+Shortbow+Shortbow = Trident
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Shortbow+Shortbow+Shortbow = Eagle's Eye
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Then we would get 8 empty combinations.
Dagger+Dagger+Hammer
Dagger+Dagger+Shortbow
Dagger+Hammer+Hammer
Dagger+Shortbow+Shortbow
Dagger+Shortbow+Shortsword
Shortsword+Shortsword+Shortbow
Shortsword+Shortsword+Shortbow
Shortsword+ShortBow+Shortbow
Hammer+Hammer+Shortbow
We could use these for other Rares, but it would just be stupid.
What could we do with those combinations?