Word of Wounding

You utter a word of ancient abyssal, a language lost to time. As an action, select a living target within range that can hear you. As your grim tongue enters their minds, their body ruptures with abyssal force - cracking blue - and they receive a wound. For each wound the target has, they take 1D4 psychic damage at the start of each of their turns. As an action, a creature can attempt to succeed on a medicine check with a DC equal to 10+ the amount of wounds they have. On a success, all wounds are healed.