Minecraft wiki entry for Combat, associated text: The guardian cannot shoot as fast as a player with a bow can, so a skilled player will be able to shoot the guardian, and then hide to break the beam's lock, repeating until the guardian is dead. Arrows will slow down and eventually fall when in water, so the player may be forced to shoot at a very close range. If the player wants to use a ranged attack, a trident is a viable choice as it doesn't slow down underwater. The main difficulty with fighting guardians is the mining fatigue effect from the elder guardians, which will slow down weapon cool-downs. If the guardian is in shallow water the player(s) can use a fishing rod to pull it out of the water where the player(s) can then kill it using melee attacks without being shot at or hurt by the spikes. The guardian can still shoot while out of the water and unless it's held still, it flops around too much to easily attack with melee.