Celeste's future favor

You conjure up a small handwritten note of pleasant prose or poetry that alludes to the future. This note gently floats towards the target creature at a speed of 5 feet per turn, doubling to 10 feet if the target creature has received damage after the casting of this spell. The slip's flight path is automatic and homes in on the target creature's current location. 

If the slip comes in contact with any creature, it dissipates and immediately shields them with temporary hit points equaling 1d12 plus your spell-casting modifier for 10 minutes. If the slip travels 14 feet or less, it's temporary HP and duration is halved, rounded down. The target creature must remain in the slip's line-of-sight and not be fully obscured or else the slip turns to ash.

The slip has an Armor Class of 11 and will be instantly destroyed by any source of damage or anti-magic effects that happen to come upon it. 

At Higher Levels: When you cast this spell using a spell slot of 2nd level or higher, the temporary hit points increases by 1d12 for each slot level above 1st.