Heroes level 10 and above is a must, the Queen's extra dps and the King's extra health will improve the kill squad's strength.
(No execution intro)
Find a suitable spot where you can force the Queen to walk to your intended path, mostly done through Army Camps, use a Wizard to create the other side of the funnel to ensure the Queen's pathing and drop the Healers.
Most likely your Queen will run through an Air Defense and sill take it down but can sometimes get one Healer killed due to their angle in healing the Queen.
Drop the Golem near the next Air Defense the path the Queen is taking, after the Mortar shell(if focused on the Golem) dropped, use 2-4 Wall Breakers depending on the wall level to access the Air Defense.
Use the Wizards to create the half side of the funnel to at least redirect the Queen to assist the kill squad.
Once Clan Castle is triggered, drop the King and then the Jump Spell and the Poison Spell to finish the CC troops off. If visualized as possible to rip through the core using the kill squad alone, drop the Rage Spell.
Beginning the air phase, drop the first two Lava Hounds on any of the two left Air Defenses.
Drop Loons in a surgical deployment to take out specific defenses.(1 for ground defenses and 2 for air/ground defenses) but be able to save a few which would be explained later.
Use a few Haste Spells to accelerate the Balloons through.
When the surviving Hound from the first sectioning flies towards the last Air Defense, drop the third Lava Hound to tank the dps in the area. Use the remaining Haste Spells to accelerate the Loons to the Air Defense.
By this time, the Lava Hounds will be dead and probably a few defenses left which is where the saved Loons come in, drop them at the back end to at least distract the defenses and allow the big pack of Loons to reach the defenses, best when a Wizard Tower remains.
Deploy the rest of the troops to assist in clean up even though the Lava Pups will be enough.
There will be times where the Rage Spell is best suited for the Queen if your goal is to take out two Air Defenses with the Queen only. 4 Healers can counter 2 point defenses/a point defense, splash and an X-Bow so do not execute the Queen Walk where there are more than 3 point defenses. The Queen can also sometimes trigger the CC and kill them herself using the Rage Spell and the Royal Cloak. In situations where Air Defenses are embedded quite deep in the base then do not use a Queen Walk as you won't get much value using the Queen, a simple GoLaLoon will be the choice.
A very reliable three star strategy but requires skill to execute correctly, the most minor mistake(i.e. A Wall Breaker fail) can cost you so don't be hasty and be patient. I also recommend watching OneHive, they're a great database for TH 8-9 war attacks.