Cain held his sword, carefully reading the Hydra's intricate movements. He doesn't have enough speed to face it head-on due to his low strength, he instead has to rely on his high intelligence to predict and dodge.
Monsters like this hydra are usually dumb, their attack mostly follows a set pattern. Cain did fight hydras in his past life and remembered their attack pattern well.
If you're standing behind it at close range, you're likely to get a tail slam attack. Be in close range in any of the other three directions and you will get stomped by its large feet. Mid-range behind it and you will get a tail swipe attack, the hydra will try to hit you with the tip of its tail like a whip. Be in any of the other directions and you will get a bite from one of the hydra's six heads. On the long-range, the hydra will try to close the distance into the mid-range.
