There are loads of hidden weapons. A lot of them are uncomplete, but some are almost complete.
With some other mods i found:
- Mantis rifle, looks like the Hornet but it shoots very slowly and is VERY accurate. I shot an NPC
in head in distance of a whole map.
-Talon pistol and machine pistol, those are pistols but shoot Fang SMG bullets.
-Zircon SMG, its complete-model SMG, works good and shoots Lapis bullets.
-Voltshot shotgun, looks like its from Falling Star or Thunderbolt family.
-Meridian shotgun, looks like a typical shotgun, shoots Trace bullets.

When playing with my Custom Sci-Fi Weapon, i found some weird bullets:
"flechette shotgun", shoots nothing.
bane rifle, looks like another corrupted weapon (like Umbra or Corruptor)
wrath- Red, glowing balls, like Power Orbs.
They are not only weird bullets, they are loads of them (about 5 more). Due to lack of time, I am unable to describe them all.

Please, add at least some of these weapons like Zircon , maybe Flechette Shotgun or even a completly new flechette SMG, or Talon Pistols. They, even uncomplete, are fun, but we need to crack the mod with other mods to get them.