Now, If you've played Borderlands one or two, you might understand what i'm saying here. In Borderlands, unique items are usually rare drops from certain foes or mission rewards, and they have strange effects, some for fun and some for combat. A good example would be the 12 pounder from the first DLC in Borderlands 2. It is a rocket launcher with high projectile speed, increased damage, it can only fire 1 rocket before reloading, and slight dropoff (It's supposed to resemble a cannon).

Now, the way this can be put into spiral knights is to do the following:

Put special levels into the clockworks that have mini-bosses at the end that have a chance to drop the item. There would be 1 per tier. At the end of a certain depth, there would be a special elevator that requires each player to pay 5 CE extra to go down. When you went down, you would be sent to the level. There would be a large variety of levels to pick from, with it's boss offering 1 unique item.

I have came up with an example of one of these unique items, with a level & mini-boss. It's called the spinner. It would be like any normal heavy weapon, but when you used it's charge attack, your knight will start spinning around. You would move as fast as you would with your shield up. Each swing would consume 10% of your shield bar, and deal 1/2 the damage of a normal swing. Other than that, it's like a trioka. The 1* variant for T1 would be called the dizzy spinner, the 3* T2 version would be called the whirring spinner, and the T3 version would be called the raging spinner (Uniques wouldn't be allowed in PvP for obvious reasons). The level would be known as the 'Spinning valleys' it would be an auora isle level, and it would consist of jellies, lumbers & gun puppies, with some shock variants. When you reach the end of the level, you would have to face a large lumber known as 'Topps'. It would have swirl markings around it's body, and the gear in it's torso would be replaced by a circular saw blade. It would fight like any normal lumber, and it would have increased health, but if you get far away from it, it will start spinning around, with it's club out, and head towards you. When you kill it, it would have a 1/8 chance to drop the spinner, and everyone in the party would get one.

I know this is a bit slapdash & all, but with some extra features put in, this would actually be great to put in SK, it would make the arcade more important and give OOO more money so they stop mocking us with battle sprites.