Curse of Lichdom

After years of research and experimentation, you have done it: created your phylactery and ascended to lichdom. Your soul immortally bound into a physical object, you gain the following effects.

• You are resistant to necrotic damage.
• While you do age, you suffer no physical or mental drawbacks from it and cannot die of old age.
• You are immune to disease.
• If you die, you form a new body within 5 feet of your phylactery after 1d10 days. Your health and all other abilities are recovered. If there is no open space within 5 feet of your phylactery, you do not form a new body until space opens up. You suffer no negative effects from not feeding souls to the phylactery while your body is unformed in this way.

Additionally, your phylactery has the following effects.

• It must be an object of size Small or smaller, but can take any form, shape, or material (so long as it is solid).
• It has 10 hit points, an AC of 20, and immunity to poison, disease, poison and psychic damage, and nonmagical bludgeoning, piercing, and slashing damage.
• It immediately succeeds all saving throws.
• If it is reduced to 0 hit points, it crumbles to dust and you die permanently.
• Once every 7 days, you must kill a living humanoid creature within 10 feet of the phylactery to absorb its soul. For every additional soul sacrificed per week, you gain one additional level of spell slots. For example, if you sacrifice 7 additional creatures after the first, you have 7 levels of spell slots, which can be divided among any number of spell slots you wish (e.g. 2nd and 5th, 1st, 1st, 1st, 4th, etc), or all sunk into one slot (e.g. 7th). Once used, these spell slots cannot be used again, and can only be regained by sacrificing more souls. If these additional spell slots have not been used by the beginning of your next required sacrifice, they fade away and are lost. If you fail to sacrifice the minimum soul at the beginning of the week, you become soul-starved and take 1 level of exhaustion. This effect stacks, so after 42 consecutive days (7 weeks) without a soul sacrifice, the phylactery crumbles to dust and you die permanently.