These would replace all item drops in boss stratums, and have very high costs associated with them. They would also be purchasable for one thousand of whatever token they require. Each upgrade would require a large number of crowns. The items aren't intended to be overly powerful, just interesting status symbols that players can strive to achieve and admire.
Snarbolax: A sword that mimics the beast bells
Description: A golden brandish-like sword made from parts of the beast bells in Gloaming wild woods.
Special costs:
2* = 1000 snarbolax tokens
3* = 100 of each beast related material
4* = 1 nightmare mane, 100 rock salt
5* = 5 nightmare mane, celestial ore
Damage type: Piercing + normal
Four hit combo- (If this is too complicated, just make it a piercing FoV with stun and beast charge)
Swipe one: Same as fang of vog's first swipe; acheron's final swipe damage
Swipe two: Same as brandish's swipe two; flourish's middle combo hit damage
Swipe three: Winmillion's swipe two but with no projectile; same damage as hit two
Fourth hit: Piercing cold iron vanquisher charge, deals stun
Charge: Brandish charge swipe (with first hit's damage), zero explosions. Rings a beast bell wherever your knight is.
Charge time: Lessens with star level
2* = Haze bomb
3* = Brandish
4* = Brandish
5* = Neutralizer
Other abilities: Damage vs Beasts: Med, for flavor
Jelly King: A bomb that spawns blast-jelly
Description: A hand-held blast jelly, ready to detonate on your foes.
Damage type: Elemental
Initial blast: Same as blast cube (not blast jelly), only effects enemies (this means you, Lumbers). Spawns jellies on explosion.
Special abilities: Isn't a shard bomb. Possibly fire?
Charge time: Nitronome
Special costs:
2* = 1000 jelly gems
3* = 100 of each slime related material
4* = 1 celestial ore, 10 dark ember
5* = 5 celestial ore, maiden's tear
As it upgrades: The amount of jelly spawned increases, as does the damage caused
Ironclaw Munitions Factory: Rocket Launcher
Description: A gun that fires a rocket in one of the cardinal directions. The rocket behaves exactly like those fired all over the place during the roarmulus levels.
Damage type: Normal
Normal shot: 1 slow moving rocket that does the same damage as sudaruska, and explodes into a small AoE
Charge shot: Same as the airstrike pickup, launches knight backwards onto their butt, old callahan animation.
Charge time: Gran faust
Special abilities: Can only fire in the cardinal directions; so up,down, left, right. Basically just snaps knight in place at all times when held.
Special costs:
2* = 1000 bark modules
3* = 100 of each construct related material
4* = 1 gremlonium ore, 10 dark ember
5* = 5 gremlonium ore, maiden's tear
Firestorm Citadel: Vanaduke's mace.. as a bomb?
Description: A bomb that makes stuff fall from the ceiling and spawns special shadow fires
Appearance: Vanaduke's mace, but smaller.
Damage: Elemental/Normal/Shadow/Fire
Special abilities: When placed, the knight drops it rather than places it, making the ground rumble a bit (and not slowing them down at all)
Bomb behavior for charging, time, etc.: Big angry bomb
When it hits the ground: A bit of the ceiling falls down, striking enemies for heavy normal + elemental damage. Spawns friendly shadow-fire that behaves similarly to the tortofist projectiles, dealing fire + shadow.
Damage: Same as tortofist but normal/elemental and shadow + fire.
Special costs:
2* = 1000 crests of almire
3* = 100 of each fire related material
4* = 1 maiden's tear ore, 10 snarbostuffing, 10 jelly glue, 10 schemer scrap
5* = 5 maiden's tear, celestial ore, nightmare mane, gremlonium
Interesting. Seem like gimmick weapons but are still interesting. I would say making the boss token cost be drastically lower - like 150 tokens, 250 at tops. Just make us need to use the material we get for guild statues in every recipe to artificially make us grind the boss more/use more tokens.
For the rocket puppy rocket launcher, I would say give it a bit of a sword combo mechanic - that is, have each shot in the normal attack be different. What I would suggest would be the primary "attack" would be a puff of smoke that pushes any monster back about 3-4 tiles (or basically a 4*/5* shield bump as an attack, and then the second hit in the "combo" would be the rocket being fired.
If this unique behavior is a bit much, then just have the rocket launcher be a 2-shot combo gun. You don't explicitly state how many shots it can fire before reloading but I can only assume a single one, and single-fire anything kind of isn't great as our weapon charge system gets shafted.
Its charge attack should be the tortofist animation - making you fly backwards - but ends with you falling on your butt like the old callahan instead of striking a pose. That would be a fun thing to play with.
I do like the idea of shadow lair materials being required for 4* and 5* items, but instead of needing "x amount of certain materials", I would say simply make the recipe one tier higher and increase the materials by 5. At 5* this means you simply need one of each shadow lair material, making an artificial 6*. You still will need 5 of the other ones you used for the previous level so I hope you like shadow lairs... Or at least buying the material.