I have a cool biome idea. It would be a new mainly pre hardmode infective 'anti-evil' from the Crimson and Corruption, which would have a chance to go with said evil on a world It would be a technical biome or chemical infected one. The ore would be aluminium.
The armor could give a chance for a stun attack set bonus.
Aluminium bars and tools would be titanium white with red or black details, and would have very space age gear to comply with this theme.
The gun for the biome would shoot homing projectiles as a normal bullet replacement, however it would have a very low dmg/shoot speed to compensate.
The magic weapon could be laser eyes - by pressing left or right and down whilst equipping the laser eyes (it would still be a weapon you out in hotbar to use), fast laser streams would come out, possesing an insanely low mana cost and damage with a superb speed and minor knockback.
The pits of the said biome (lets call it The Data Biome) would be angular and turn frequently. Altars would instead be Onboard Computers. The centre of these pits would be in the shape of a giant cog, with a huge circular solid block in the middle. This would add to the interest of the boss i have thought of...
The boss would be a mechanical spider or arthropod, which would have no minions but instead would shoot projectiles. It would be a solid block boss but a strange one - it would walk, but also on the sides and even the ceiling! It would also jump from outer to inner circle (the center pit would be very large by the way).
That is all for now! I accept suggestions and will add much more to this concept if you wish (i.e terrain, mobs, etc)
BTW: I am not a good spriter, however I might load up drawings of ideas.