"Meta-Mind learned the Light Slash Skill, allowing him to embed light-based magic in his physical strikes with little to no mana!" -Turn 4 Summary, Wave 4
The Light Slash Skill allows its user to infuse any bladed weapon with light energy, adding damage to the attack on top of its regular physical damage. It combines very well with most sword Skills, though it is unknown if it is compatible with Dark-based Skills.
How to LearnEdit
As the Skill's only current user, Meta-Mind, learned it through level up, it is unknown how to learn the Skill. It is likely, however, that merely focusing on combining light-based abilities or magic with sword combat will enable the user to learn this Skill.