I've sprite-edited these shitty swords in attempt to show you what we would be able to make with new biome ****.
Here's what I named most of them.
Earth: Diamond, Gold(A.K.A Impractical Materal), Iron, Stone, Wood Stick/Wood Sword. (Wow, did I really do that?)
Fire: Fire-sword, Heatened Stone-sword(A,K.A Equivalent to stone sword but can set **** on fire.), Hellstone-sword(those red **** on the ground in the screenshot), Soulstone-sword(the one with creeper faces), Wood Sword
Water: Sapphire Double-trident, Coral sword(A.K.A Impractical Sword), Sapphire Trident, Metal Trident, Metal Stick
Air: Regisword(2 points if you get reference), Golden Edge Sword(A.K.A Impractical Dagger), Iron Ninja Sword, Chrome Ninja Sword, Metal Stick
Explanations for them:
Earth swords are shitty swords you store in refrigerators because they don't make them explode or anything.
Fire swords are 20 times stronger and have a chance of setting **** on fire.
Water swords are stronger than fire swords and they can catch fish.
Air swords are in between Earth and Fire but they allow you to double-jump, run and climb walls.
This is an interesting idea, but a lot of people will say no, because they don't like the "magic" type of idea... I am fine with it, if he's putting in goblins or dragons, you can't say "absolutely no magic." However, not now... During the full game this would be a great idea, just not now!
Soulstone Blade is better... It should be a unique weapon crafted from the Soul ores found 100+ blocks deep in Hell mode, and requires you to hunt a formidable (but not insanely impossible to kill) monster that can be found in the tunnels...
Maybe a Lich? They are what you would call manipulators of souls, so you could have a material for the hilt of the blade.
The Lich count as a boss monster, spawns in a specific kind of area, protecting a item that's stuck on the altar. The boss can shoot out a ball of plasmic energy at you, dealing moderate damage and slowing your movement for a few seconds. The projectile moves a bit slower than you'd think, making it possible to dodge. If you get hit by the projectile, the Lich would attempt to drain your life by 1 hearts per second, by walking up to you and "sucking" out your life through a beam.
Hitting the Lich will make it flinch, and forces it to use a melee attack to knock you back.
Soulstone Blades may be a unique wewapon that only works in Hell mode, and when used in the normal biome, it will be as strong, or 50% stronger/durable than a iron sword. When used in Hell mode, it is as strong as diamond, with the ability to steal the enemy's life to your own at a 2:1 ratio.