the only way to make a ninja back off is very hard,since you will need to have very powerfull towers to hold him until his 5 seconds of shadow mode is off,then use the speed up spell on all towers to try have a chance against him
to kill the baron,equip disrupt in your action bar 5 or 6 times,when you disrupt him,he damages himself to recover focus,so keep doing this until he dies and if you have some luck you will get his sword
please keep this comment alive and give a + so people can see it
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