to kill the tank throw a grenade you start out 5 when you start the level the he will be exposed you can shoot him for about 3 sec then he will go back in hope this helps
i found the aprentice with grade 30 students battle starts he just syands for 2 min hes still alive he atacks and hit me for 241 and killed all my gys in 2`4 hits VERY HARD
 "Bunny Invasion 2"){kind=icon}
 "The Idle RPG"){kind=icon}
 "Valthirian Arc"){kind=icon}
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 "Deadly Neighbours"){kind=icon}
 "Kids Vs. Santa"){kind=icon}
 "Dragon Boy"){kind=icon}
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 "Frontier"){kind=icon}
 "Arcuz (Full Version)"){kind=icon}