Guardian Scout II
The Guardian Scout II is an enemy which appears in Breath of the Wild.
"Although originally designed by an ancient civilisation to combat Ganon, these scaled-down Guardians were placed inside shrines as part or the trials. In addition to the beam functionality, this particular model was designed to handle weaponry as a means of further testing the combat prowess of one undertaking the trials. It takes some serious skill to go toe-to-toe with one of these."
They have 375 HP and wield a Guardian Spear, Guardian Sword, or an Ancient Battle Axe. The configuration of its weapons and whether or not they also wield a Guardian Shield depends on the instance of this enemy you encounter, though they only ever hold one weapon at a time.
The Guardian Scout II may start attacking with either its weapons or its laser ability. It will likely switch strategy mid-battle to catch you off guard; this can happen when its health drops to a certain amount. When it uses it's laser ability you can parry the pulse with Links shield using a Perfect Guard to reflect the projectile back at the Scout.
When facing this scout in a Test of Strength Shrine the scout will use a wide variety of attacks. The scout may stop attacking Link at close range and jump far away. Be prepared to find a stone pillar or to create an obstacle to hide behind as the scout will extend it's weapons and come spinning towards Link. You can also stop it spinning before it hits you with a precise shot in the eye with an Arrow. Once the scout has stopped spinning it will take a moment to regain itself, leaving you time to attack it.
Another attack the scout may use is it can retract its upper part into its body and spin its eye around making a laser. This renders a circle of the battle field harmful and will knock Link back if the circle is too close. However the spinning motion also creates an up draft which can be used by Link to get some height above the circle and attack from above with a melee weapon. Another way of stopping the scout spinning is by carefully firing an Arrow into its eye. This is difficult to pull of though because its eye is spinning rapidly timing is crucial to land a hit on the eye.
When the scout drops to a very low health the scout will become stationary on the battlefield and will charge up a beam to fire at Link, similar to the attack of a Guardian Stalker. A well timed Perfect Guard can reflect this beam back at the scout, but if not timed correctly then the beam will either hit Links shield and likely destroy it in one shot or the beam will hit Link causing a large amount of damage. The two outcomes will depend on whether you missed the Perfect Guard by parrying to early or too late. Once the scout has charged up it will not only fire one beam, but multiple consecutively before charging up again. Fortunately the scout can only aim so fast, so running around the scout in circles while it is firing will usually cause the scout to miss because it cannot turn fast enough to aim at Link properly. While the scout is charging it is open for attack so make use of that time. If the scout is about to shoot then you can run around it to dodge, find something to hide behind (it will break stone pillars after the first shot leaving you open to be hit on the consecutive shots), be prepared to parry its beam, or try and shoot an Arrow in its eye to stun it, though the latter can be tricky to do in the short amount of time available.