There are plenty of helmets and armors based on enemies found in the Clockworks. Why are there none based on Gun Puppies? Come on, everyone loves Gun Puppies, right? Also the Love Puppy Disguise exists, so there's already a model that can be used.
These helmets (yes, only helmets and not armors) are designed to be very unorthodox in terms of abilities. Spiral Knights could use some more variety in its defensive items! Anyway, they're primarily for pure gunslingers, which makes sense considering the enemy they're based on.
(Note on values for resistances: I'm using what appear to be the standard values on defensive items. The Spiral Plate Helm line is a good reference for both resistances and weaknesses. For examples, a 3* weakness is equal to the Boosted Plate Helm's weakness to Sleep, and a 4* resistance is equal to the Heavy Plate Helm's resistance to Stun.)
Gun Puppy Helm
3*
Possible description: Headgear resembling a Gun Puppy! It's extremely cumbersome to wear and the technology is far from perfect, but knights looking for a massive boost in firepower need look no further.
Defenses: Same as the Angelic Helm but with shadow changed to piercing.
Resistances: 3* weakness to Stun.
Abilities: Attack Speed Decreased low + Movement Speed Decreased medium + Handgun Damage Bonus very high
After this, the line splits into either two or three different choices.
Rocket Puppy Helm
4*
Possible description: A dangerous helm intended only for knights with a dangerous affinity for projectiles.
Defenses: Same as the Seraphic Helm but with shadow changed to piercing.
Resistances: 4* weakness to Stun.
Abilities: Attack Speed Decreased low + Movement Speed Decreased medium + Handgun Damage Bonus very high
Roarmulus Helm
5*
Alchemy cost includes one Level 10 Rocket Puppy Helm and one Spark of Life.
Possible description: This marvel of reverse engineered gremlin technology bears all the upgrades possessed by the Roarmulus Twins in comparison to Gun Puppies, minus the size and firepower. So that leaves... defense and speed. These are still very useful!
Defenses: Same as the Valkyrie Helm but with shadow changed to piercing.
Resistances: 5* weakness to Stun, 5* resistance to Shock.
Abilities: Attack Speed Decreased low + Movement Speed Decreased low + Handgun Damage Bonus very high
Red Rover Helm
4*
Possible description: This helm is infamous among knights due to how uncomfortable it is to wear. Heavy and hot, at least it provides very heavy ordinance and a resistance to getting even hotter.
Defenses: Same as the Seraphic Helm but with shadow changed to elemental.
Resistances: 4* weakness to Stun, 3* resistance to Fire.
Abilities: Attack Speed Decreased low + Movement Speed Decreased medium + Handgun Damage Bonus very high
Red Roarmulus Helm
5*
Alchemy cost includes one Level 10 Red Rover Helm and one Gremlonium.
Possible description: Behold the Crimson Order's most terrifying war machine! Now in knight-sized form.
Defenses: Same as the Chaos Cowl.
Resistances: 5* weakness to Stun, 4* resistance to Shock, 4* resistance to Fire.
Abilities: Attack Speed Decreased low + Movement Speed Decreased low + Handgun Damage Bonus very high
The last possible choice when the line splits would probably require a different base model. The one used for the Chroma Mask line would hopefully work.
Howlitzer Helm
4*
Resembles a T1 Howlitzer with cracks in the skull.
Possible description: This creepy canine cranium cracked considerably when crafted, creating concerns connected to its capacity for cushioning critical concussions in combat. Basically, the bones didn't properly fit the frame of the Gun Puppy Helm. But they are much lighter than metal.
Defenses: Same as the Seraphic Helm.
Resistances: 5* weakness to Stun.
Abilities: Attack Speed Decreased low + Handgun Damage Bonus high
Mercurial Howlitzer Helm
5*
Resembles a T3 Howlitzer with extra effects similar to those on the Dread Skelly Mask, specifically glowing eyes (on the helm's eyes, not the knight's) and ghostly aura.
Alchemy cost includes one Level 10 Howlitzer Helm and one Reaper Rib.
Possible description: This savage skull will send you speeding at your opponents like a Howlitzer set loose! Also you'll shoot powerful bullets instead of exploding. This is an important distinction.
Defenses: Same as the Valkyrie Helm.
Resistances: 5* weakness to Stun, 3* weakness to Shock, 3* weakness to Fire, 3* weakness to Poison, 3* weakness to Freeze.
Abilities: Attack Speed Decreased low + Movement Speed Increased low + Handgun Damage Bonus high
This turned out to be a very difficult line to try to balance. The massive handgun damage bonus (and MSI on the Mercurial Howlitzer Helm) had to be properly balanced out. So these helms ended up with a similarly massive number of drawbacks, such as ASD, MSD, status weaknesses and minimal defenses.
Suggesting a set of new items is a bit of an experiment on my part and I'm very interested in feedback about all this! Would anyone actually use these helms if they were put in the game? Do any seem overpowered or underpowered? Do the "possible descriptions" entertain? Do you have any suggestions? Let's make this a discussion. :)
They already exist and will never be anything beyond costume if they ever implement it. You can find them in the game files along with Trojan, Gremlin, and Zombie heads. This also horribly balanced with a stupidly high damage bonus offset by an absolutely miniscule speed reduction.