This article's content is accurate to the most recent public game version, 0.4.8d.
Cost: 10 MP
Source: None
Ultrasonic Shriek is a spell that deals strong 
Wind damage with a 50% chance to inflict the 
Stunned status effect to all enemies. Despite being a spell, it scales with ATK and DEF, and cannot be evaded or nullified.
Yoshida uses a unique version of this spell that targets two random enemies instead of hitting all enemies.
The following enemies can cast Ultrasonic Shriek: