Esta Network is a premium PvP based Minecraft server that is still in development, but already published as a release. Right now the main gamemode is Bot Practice, built for players who want to sharpen their fights and warm up before jumping into real matches.
Bot Practice runs on 1.7 to 1.8x combat and uses an AI dueling system. The bot is self learning, so the more it gets played, the better it should perform over time. It is set up through an NA proxy as well, so players can jump in and practice from there.
The server is still growing, and more content is likely to come later. For now, Esta Network keeps the focus on PvP practice and duels, with the website still in development and the community handled through the and store links.