Fun game i created / any ideas of what abilities i should give the enemies that chase the player

Please dont try the tutorial, this explanation will be enough so please read it carefully.
This game is like Pacman as your goal is to collect all the shards. Four knights will chase you as you start to collect more shards. The red, blue and green knight currently just run around hunting you. The last knight that activates is the red/skull knight don’t stay in his green radius for too long or the bar on your screen will fill up, and when full you will die, the good thing about the red knight is that he does not move as fast as the others so you can easily avoid entering the radius. After a certain amount of time it will start to rain, if you do not press the button in a certain amount of time you will die. I’d highly recommend you play easy or medium mode first and figure out the map layout, how the knight moves and most importantly how to find the button when it is about to rain. Good luck and any ideas will be appreciated.