And here's a description of what a wither storm is :
The Wither Storm Is A Dangerous Creature That Destroys The World. It's Created By 3 Wither Skulls And Soul Sand+Command Block. When Created, The Wither Storm Will Pick Up Blocks And Eat It, It Will Become Bigger And Bigger Until It's Going To Destroy The World, Phase 4 Has 3 Heads With 3 Tractor Beams That Can Pick Up Mobs And Players And It Has 5-8 Tentacles That Can Attack Players And Destroy Whole Buildings. In Phase 5 There Are 2 Extra Large Tentacles The Wither Storm Also Can Use To Destroy Things, And The Back Of The Wither Storm Also Grows, (An Example Of That : https://youtu.be/PvL3S9ILlpU?si=KoDGFu4MFkFju3Pz&t=694
And To Kill It Use A Super Powerful Bomb, Also Known As A Formidi Bomb, Which Is Made By Combining 8 Gunpowder With A Super-TNT
But It's Not Over Yet... When You Come Closer It Comes Back Alive And Continues To Destroy The World, But It's Split In 3 Wither Storms (One Is Big And The Others Are Small) But These 3 Can Regenerate 2 Heads So Then They Have 3 Heads!?!?
To Defeat The Wither Storm Go Inside The Wither Storm And Find The Command Block... And Then Use Your Enchanted Command Block Item To Damage And Break The Command Block