Anti-Magic Mask

Anti-Magic Mask (抗魔の仮面) refers to a mask first seen to be owned by Hero Chronoa. It was given to Shizue Izawa to suppress Ifrit, who resided inside her. It was later passed down to Rimuru Tempest upon Shizue's death. Rimuru then gave it to Chloe Aubert as a parting gift after his time as her teacher was over.

While the real mask was in the hands of Chloe, Rimuru was still able to duplicate a working copy of the mask, though Rimuru modified it to only have the Magic Resistance ability in strengthened form, as the other abilities were useless to him.

Ability
The mask is a magic item infused with four effects:
 * Magic Resist: Dulls any magic attacks that the enemies cast and hide the user's internal magical force.
 * Antidot: Nullifies poison that made contact with the user.
 * Breathing Support: Allows the user to keep their lungs full even if the flames consumed the oxygen around the user.
 * Amplify Senses: Increases the user's senses.

At the end of the battle between Shizue and the Black Primordial, Noir, the latter suspected that the mask might be capable of suppressing time, a trait he referred to as Infinity.