If Battle Pirates is lagging and you've already tried running through the basic troubleshooting steps, there are a few more things you can try; the following three steps will address the most common factors contributing to lag.
- Plug your computer directly into your router or modem using an ethernet cable.
- Ensure no other applications or webpages are running in the background.
- Test your network connection by running a Traceroute.
Some steps above link to an article that should walk you through the process.