There really isn't any possible way to make something "Faster" without some requirement of transaction.

However, that doesn't mean there are some things that could make a slight difference:

*Try installing a 64-bit Version of Java into Spiral Knights, there are various tutorials on doing so.

*Try closing out various windows when running Spiral Knights, often if not, various processes will eat at your Ram (depending on how much you have) and closing out most windows can usually help speed up a game you're playing.

*Try lowering your quality to the lowest settings: 640x480, disable V-Sync, enable cull transients, enable compatibility mode. disable render effects. 640x480 renders the smallest amount of pixels and will usually speed up the game.

*Try Extra.txt in your Spiral Knights folder, there's tutorials on this in various places but it should help you divert more resources to the game.

Make sure your Antivirus isn't interfering with the game, I had this before (and still do with any Antivirus) is that it increases my already bad latency and I often desync with the game. Allow an exception to Spiral Knights.

*Make sure you're not downloading anything while playing the game, this will often cause slowdowns and internet speed being decreased by a major amount.

*Check what server you're using, a large portion of Spiral Knights players use the US server, the EU sever (depending on your location) will either help or make it worse. You can change this setting in options.

These are really the only options you have if you're not willing to spend any money.