The ServerTick Event is fired every tick on the server.

You will need to cast the event in the function header as this class:
crafttweaker.event.ServerTickEvent
You can, of course, also import the class before and use that name then.

Event interface extensions

Link to event-interface-extensions

WorldTick Events implement the following interfaces and are able to call all of their methods/getters/setters as well:

There is no additional information besides the information mentioned in the interfaces above.