School of Neo-Necromancy

The School of Neo-Necromancy focus is more on harnessing their control over life and death to prolong their own mortality, as opposed to simply hoarding forbidden power. Some harness this knowledge of life and death for good, while others use it exclusively for selfish ends. Regardless the school collectively strives to embrace the more acceptable uses of their unnatural power. 

Artificial Vigor

When you take this school at 2nd level you gain an advances understanding of how to manipulate the forces of life and death. You can cast False Life on yourself without using a spell slot. When you do this cast the spell as though you were using your highest level wizard spell slot. So a 3rd level wizard could cast this as though they were using a 2nd level spell slot, and a 10th level wizard can cast this as though they were using a 5th level spell slot.

Once you use this you cant use it again until you take a long rest, or reduce an enemy to 0 hit points using a necromancy spell. 

Basics of Undeath

You learn the basics of how to prolong your life. When you gain temporary hit points through a spell or other means these hit points do not expire until the end of a long rest.

Necrotic Fortitude

Your efforts to subdue your own mortality have become more nuanced. While you have temporary hit points you are immune to poison damage, also you have immunity to disease, exhaustion, and can hold your breath indefinitely. 

Arcane Vitality

Starting at 6th level, you can store magical energy within yourself to prolong your life.

Whenever you successfully end a spell with Dispel Magic or Counterspell, you gain an extra use of Artificial Vigor. 

Neo-Litchdom

Your capacity to extend your own life has breached all know bounds. If you gain temporary hit points and already have temporary hit points, you do not lose your old temporary hit points.