There is a really good game guide built into the game itself, it is definitely worth looking through this. It explains how battles, engagement, Line of Sight and most other aspects of the game work really well.
There is also an overview on the official website: Game Guide
Chaos Reborn is easy to pick up but difficult to master. There is luck involved, but a real wizard makes their own luck, use the guides below to get a head start on avoiding those easy deaths and optimizing your battle strategies.