Lisa Turpin reached up toward the faint pecking sensation at her neck, only for the Mage Armor still active on her to deflect her hand to the side. Then she came back to herself and realized she was safe and sound.
"These two defensive spells are actually nowhere near as strong defensively as Protego. As you all saw, aside from Shield being a sort of counter-spell specifically aimed at Magic Missile, its defensive effect against other magic is about the same as a Muggle-made Tower Shield. Mage Armor is similar, roughly equivalent to the protection of Muggle Plate Armor." Allen withdrew his wand and explained the two spells to the students. He pointed at the feather on Lisa's neck and the slightly reddened peck marks. "Also, because the spell components of these two Charms do not contain any dispelling element, the help they usually provide is physical in form, created by force fields. Their usefulness is limited against Charms whose magical effects are produced directly by magic power... Though they will improve somewhat as your strength rises, that improvement is more in other areas rather than in defensive effect. If a deflected Charm happens to be knocked away at the wrong angle, it's hard to avoid some fish slipping through the armor's net... So a protective Charm like Protego, which can also defend against most magical effects, is a skill you must continue to master."
The Wizards below the stage, who had just been getting excited, suddenly looked disappointed. Some of them did not understand why Allen would want to teach them defensive magic that was not as good as what they had originally mastered.
"What? Curious why I would have you practice these two defensive Charms with limited use?" Allen smiled at the Wizards, then held up one finger.