They have an artificial restriction of 200ms for their reaction time, and their actions per second is similar to human players. The main information the bots have that players don't is exact coordinates of everything they can see, and the amount of damage attacks and spells do. The bots know with 100 percent certainty that a spell or attack is in range before they use it, whereas the human players would have to base it off visuals, or press another button to bring up their spell's range indicators. Having the damage of attacks memorized allows the bots to know if an incoming projectile will kill them, that allows them to not waste healing resources if they know they'll survive. The bots also move based on coordinates, so misclicking and mouse travel time aren't an issue for them.