Invoker is basically the easiest hero ever.
If you want to be a man, play my guide.
Spells are for wimps, man.
Buy Blades of Attack, perhaps invoke ghostwalk, just harass and get last hits.
Eventually you might want to switch your instances to more exort/wex for more dps.
Use ghostwalk to escape tricky situautions.
Sunstrike can be invoked during a chase to burst down enemies.
Mostly though, just skill exort, wex, and stats so you get more damage.
Just buy the items I listed. If you can't afford them, look at the dollar menu for Manvoker.
Once you got your items, just walk around right clicking and ks ing with sunstrike.
Try to get a high kd and win.
You are welcome for the Battle points.