D&d False Life at Life

D&d False Life. 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. While this spell is in effect, you gain temporary hit points equal to 1d10 +1 per caster level (maximum +10).

5e false life is a 1st level necromancy spell from the artificer, sorcerers and wizards spell list. Therefore, it, and as far as i know only it, will stack with false life. If you're at 12/12 hp and cast false life and get 8 temp hp you're at 12/12 hp + 8 thp.

Ironlands Dark Sun Hack for ACKS

False life 5e is 5 th edition dnd powerful spell, that allows you to put powerful 1d4 impact on your evil creature enemies. However, false life would be of more utility because (1) it can be cast before heading into danger and forgotten, (2) doesn't consume a valuable combat action, and (3) that's about it. With a necromantic facsimile of life, you have to blast yourself then you will gain 1d4+4 temporary hit points for the duration. By using the spell slot of 2nd level or higher you can cast false life 5e spell then you will gain 5 additional temporary hit points for each and every slot above the 1st level.