Source: Player's Handbook
1st-level necromancy
Casting Time:
1 action
Range:
Self
Components:
V, S, M (a small amount of alcohol or distilled spirits)
Duration:
1 hour
Bolstering yourself with a necromantic facsimile of life, you gain 1d4 + 4 temporary hit points for the duration.
At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, you gain 5 additional temporary hit points for each slot level above 1st.