Partial Possession

Liches are creatures that cling to immortality with all their might. With their magical powers they try to live forever, but many fall victim to adventurers. A rare few have found a way of saving their soul at the last moment. When they are about to be destroyed, they send their soul away to find a new host. This must be a creature that is weak enough to be possessed but strong enough to handle the liches magical powers. This often leads to possession of very young children. The possession is not perfect and rarely ends with full control over the victim. In time the victim learns to tap into the lich’s magic powers and is able to borrow them to use spells. The lich's soul, however, will never stop to try to take over the host’s body. Many of its followers will search for the possessed body to help the lich take control. As both the victim and lich become stronger, their bond grows ever more powerful. The victim gains more control over the liches power and in turn lich can use its power to protect its future body and try to take every opportunity to gain control.

Lich’s magic

Starting at 1st level, your magical power comes from the lich’s soul within you. When you use it to cast spells the connection becomes stronger and the lich tries to take control, but it can never take over your body this way and only ever manages to cast its own magic.

When you cast a sorcerer’s spell of level 1 or higher, you must first make a wisdom saving throw, for which the DC = 5+the spell slot used to cast the spell. If you succeed you cast the spell as intended, if you fail the lich casts one of its spells. That spell is selected by rolling a d4 and using the spell of the corresponding level as the slot used as shown in the tabel below.

 

Spell level	1	2	3	4
1st	Detect Magic	magic missile	shield	thunderwave
2nd	detect thoughts	invisibility	acid arrow	mirror image
3rd	animate dead	counterspell	dispel magic	fireball
4th	blight	dimension door	blight	dimension door
5th	Cloudkill	scrying	Cloudkill	scrying
6th	Disintegrate	Globe of Invulnerability	Disintegrate	Globe of Invulnerability
7th	Finger of death	Plane shift	Finger of death	Plane shift
8th	Dominate monster	power word stun	Dominate monster	power word stun
9th	power word kill	power word kill	power word kill	power word kill

 

The target for the new spell stays the same as the one you selected when trying to cast your spell. If the selected spell uses a special target (like animate dead) and a target is available it uses that target instead. If there is no appropriate target for the spell you must reroll the d4. The only acception to this is the Counterspell spell, which is saved to use against the first spell cast that can be a target, without using your reaction. The lich’s spell doesn’t care if the spell hurts any of your allies.  

When you gain Meta Magics you must choose to use them before roll your Wisdom save. The Meta magics are also used with the lich’s spell.

Precious Vessel

Also at 1st level, the lich wants you to stay alive and will try to stop anyone from harming you. When a creature makes an attack roll against you roll a d20. If you roll 20 on the die then the lich casts the Frostbite cantrip. It also uses your reaction (if you haven’t used it) if you have a first level spell slot left, to cast the Shield spell.

Resist and Protect

Starting at 6th level, both you and the lich have becomes somewhat stronger. You are more capable of resisting the lich and the lich can access your sorcery points to better protect you. You have proficiency with Wisdom saving throws. In addition, when the lich tries to cast the shield spell as part of the Precious Vessel feature and you don’t have any level 1 spell slots left, it uses 1 of your sorcery points to cast the spell. If you don’t have any sorcery points left it uses the lowest spell slot you have available to convert it into sorcery points as per your Font of Magic feature.

Lich’s Resistances

Starting at 14th level, you can temporarily make use of the lich’s resistances to shield you from certain damage types and effects. When you would take Cold, Lightning, Necrotic,  Poison damage or Bludgeoning, Piercing, or Slashing damage from non magical Weapons you can use your reaction to gain resistance against the damage. Alternatively, when you failed a save roll against  being Charmed, Frightened, Paralyzed or Poisoned, your can use your reaction to reroll the save with advantage. Using this feature gives the lich more control. The turn after you used this reaction you must use your action to cast a 1st level spell or higher automatically failing the Wisdom save of the Lich’s Magic targeting a random creature unless it needs a specific target.

You can’t use this feature if you don’t have any spell slots left.  

Lich’s Powers

Starting at 18th level, you are able to tap into the Lich’s special powers by using your sorcery points and the lich is able to take control of your body when you can’t fight it anymore.

You can use 6 sorcery points to use the lich’s paralyzing touch. Make a melee spell attack, on a hit the target takes 3d6 Cold damage and must succeed on a Constitution saving throw or be Paralyzed for 1 minute. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

In addition, when you are reduced to 0 hit points the Lich takes over your body. Immediately after the current turn you regain 20 hit points and directly take your turn (repositioning your place in the initiative order). During your turns the DM controls your actions (or tells you how to play the lich). When you are reduced to 0 hit points again you aren’t incapacitated but instead must make death saving throws according to the standard rules. Once the lich/you fails 3 death saves it can no longer maintain control of your body and you fall to the ground as if you were reduced to 0 hit points.