Gatekeeper's Tattoo

Alter: While this tattoo is applied on your skin, you can speak the tattoo’s command word to create a 10-foot-radius aura around you that lasts for 10 minutes (no action required). You and all creatures friendly to you in the aura have advantage on saving throws against spells and other magical effects. All creatures hostile to you in the aura have disadvantage on saving throws against spells and other magical effects. Once used, the tattoo can’t be used again until the next dawn.
While the aura is active, you can use a bonus action to draw the aura into the palm of your hand, sacrificing its protection to engulf your weapon in ink and darkness. You gain a +3 bonus to attack and damage rolls made with this weapon. On a hit, it deals additional necrotic damage equal to 2d8 and has the finesse, light, and thrown properties (range 20/60). The ink vanishes after your aura would have vanished. For the duration, you can use your bonus action to dismiss the ink and recall the aura, or vice versa.

Attunement: yes
Materials/cost: 14400gp
Placement: Torso
Rarity: Very Rare
Produced by a special needle, this magic tattoo represents an immortal, insidious creature, a pride demon.

When examined by a curious druid, she discovered that this tattoo actually had a secondary property that makes its bearer’s body secrete an interesting aroma. The aroma seemed to have an effect on other creatures’ minds. This meant that in addition to the tattoo’s ability to alter the magical defenses of whatever is in the vicinity of its bearer, it also altered their behavior in subtle ways if exposed too frequently to the tattoo’s aura. Whether those changes are permanent remain to be seen. The druid continues her research to this day.