Still Surface

While wearing this brooch, you appear entirely human to casual observation and to all divination magic of 6th level or lower. Your genasi traits, luminescent skin, aquatic coloring, the faint scent of brine, or any other visible, audible, or olfactory marker of elemental heritage, are imperceptible to others unless you choose to reveal them. You also have advantage on Charisma (Deception) checks made to conceal your identity, your origins, or your nature. Spells and effects that would reveal your true form or creature type (such as detect evil and good or true seeing cast at 6th level or lower) perceive only a humanoid of the type you wish to appear as.

Borrowed Memory

Once per dawn, you may spend 1 minute performing, singing, playing, or speaking, for a creature that can hear and understand you. At the end of the performance, the target must succeed on a DC 22 Wisdom saving throw or its memory of you shifts. You choose one of the following alterations: the target forgets having met you entirely and believes it has simply never seen you before; the target remembers meeting you under a different name and appearance of your choice (a face it cannot quite describe); or the target believes you are someone it trusts, a name from its own past that it supplies from memory. The false memory is seamless and resists casual scrutiny. A greater restoration spell or a successful DC 22 Intelligence (Investigation) check made while the target has a specific reason to doubt the memory restores the truth. This effect has no duration, it persists until dispelled, and the saving throw is Wisdom-based against your performance.

Depth Resonance

Your voice carries the sub-audible pressure of deep water. When you use Bardic Inspiration, the recipient gains an additional benefit: the first time they use the Bardic Inspiration die, they may add it twice and take the higher result. Additionally, whenever any creature within 30 feet of you that you can see makes a Charisma saving throw, you may use your reaction to grant that creature advantage on the roll, the brooch hums almost inaudibly as the cold weight of the deep sea steadies their resolve.

The Undertow

Once per dawn, you may speak a single word in Aquan as an action, directing it at one creature you can see within 60 feet. A cold current seems to pass through the air between you. The target must succeed on a DC 22 Charisma saving throw or become overwhelmed by a sensation of drowning, not physical harm, but the primal terror of sinking beyond sight of the surface. The creature is frightened of you for 1 minute. While frightened in this way, its speed is reduced to 0 and it cannot speak above a whisper. At the end of each of its turns, the target may repeat the saving throw, ending the effect on a success. Creatures that do not need to breathe or that are immune to the frightened condition are unaffected.