Screech Alpha (スクリーチ「α (アルファ)」, Sukurīchi "Arufa")[1] is an attack used by Crona and Ragnarok.
Overview[]
This attack is very similar in structure to Screech Beta, as it also assumes the form of a mouth, but it is instead launched at the enemy as a projectile. It grinds through the floor, causing heavy destruction as it does so, while heading towards the enemy. It will explode at any time when it makes contact along its path. The majority of the attack features a black color surrounded by a purple aura. This attack was first demonstrated by Crona against Maka Albarn in their intial fight.
Variations[]
Aerial[]

Crona using the aerial version of Screech α against the Oldest Golem.
The attack itself is not confined solely to the ground but can also be launched as an aerial projectile. Under these conditions, the attack will try to "consume" the opponent using its mouth and encompassing as much of their body as possible before detonating.[2]
Black Dragon Resonance[]

Screech α's appearance under the influence of Black Dragon.
When used with the Black Dragon resonance technique, its power is drastically increased. In this circumstance, the attack doesn't employ its "mouth" to inflict damage but instead radically reduces its width, until the form is entirely flattened to create razor-sharp edges around its exterior. Due to the force at which the ability is launched, it easily slices apart the intended target and anything else in its path, before erupting in an enormous upward and similarly shaped explosion.[3]
Kishin Fusion[]

Enhanced Screech α after absorbing Asura.
After Crona became a full-fledged Kishin and swallowed Asura, they displayed the ability to use what appears to be far more powerful Screech α using the Abyss of Despair & Uncleanliness and the Darkness by swinging all three blades against the ground in conjunction. This results in the attack having a more monstrous, smoke-like appearance with multiple sets of glowing ghostly eyes and two mouths with multiple rows of teeth. The effect of this version of the attack is unknown as Black☆Star was able to dissipate it in one strike.[4]