you can do it in many ways actually. I've done it through speed agility and defense /speed defense and strength/reproduction speed and strength/reproduction defense and strength. I've completed the last 5 eperiments using those combos maxed out (mostly maxed out).
 "RED CODE"){kind=icon}
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 "Post it Draw it"){kind=icon}
 "Phage Wars 2"){kind=icon}
 "Bloons Tower Defense 3"){kind=icon}
 "Doom 1"){kind=icon}
 "CycloManiacs"){kind=icon}
 "City Smasher"){kind=icon}
 "Multitask"){kind=icon}
 "Guardian of Man"){kind=icon}
 "UPGRADE COMPLETE!"){kind=icon}
 "Dark Cut 3"){kind=icon}
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