Emergency Rune of Healing

(To create the rune, you hold the needle to your skin (or other willing creature) where you want the tattoo to appear, pressing the needle there throughout the casting process. Utter the spell incantation. When the casting is complete, the needle turns into the ink that becomes the tattoo, which appears on the skin.)

The rune is created at any time, and can not be activated before
one full day has passed.

While you have the rune, you may store any amount of hp into the
rune that you wish, (which will be removed from your hp, as damage taken.)

After one full day, if your hp drops to 1hp, you may touch the rune, say the command, and regain any hp stored in the rune,(up tp full hp), which will in turn cause the rune to disappear from your body, losing any remaining hp stored in the rune, and requiring another Emergency Rune of Healing to be needed for future uses.

(casting this rune 5 times on the same player ,in the same place on the body, will cause the rune to be permanent, not requiring it to be cast again, or losing the extra hp in the rune after use.) (can also be made permanent by casting permanency spell on the rune immediately after casting the rune.)