The image becomes warped (distended) as Luka uses Fallen Angel Dance
A secret skill to unify a holy wave and avoid attacks. It seems particularly effective against angels.
"Infallible and unfailing... The Dance of the Fallen!" - Luka
Fallen Angel Dance is a skill which Luka activates under the influence of holy power. When attacked, Luka will mysteriously evade it. The effect used is a shorter version of the "sleep waves" as Luka is falling asleep in the beginning of the game just before he speaks with Goddess Ilias.
In Chapter 3, Luka finally awakens his angelic powers against Archangel Ranael and can use Fallen Angel Dance. This particular move is extremely effective against angels, however it is not effective against monsters. It has wind-like properties similar to Sylph, and once he regains her after defeating Dominion Endiel, the two wind abilities are merged.