Domain Expansion: Witches Cottage

You create a demiplane centered on yourself. This demiplane is the ultimate spell in terms of both defensive and offensive capabilities, and mimics the power of a Witch, Wizard or Warlocks Hut or Cottage. To the outside world this area looks like a cube of greyish black smoke (this cube functions as a massive, cube-shaped Wall of Force). Every creature in the 60 foot cube's radius when this spell is first cast must make an Intelligence saving throw against your spell save DC. On a successful save the creature appears just outside of the spell range in an unoccupied space. On a failed save the creature is swallowed within the demiplane, trapping it inside for the entire duration. Any creatures outside or inside the cube cannot enter or exit it by any means, including teleportation magic. 

Terrafirma. The demiplane looks like however you like. You control the environment and you can choose whether or not to harm any creature in the demiplane. As an Action on your turn, you can change the environment/layout of the space within the 60 ft cube, as if casting the spell, Hallucinatory Terrain, in tandem with the spell, Major Image. These illusory landscapes and changes count as 'pseudo-real' within the domain.

When you first cast the spell, you can select any 3 'lair' or 'domain' effects from the list below, as part of the casting Action (if the spell is successful in capturing the enemy). The effects detailed below use the DC or spell attack bonus in the description, or your own spell save DC and spell attack bonus - whichever is higher. In addition, you can choose to roll the damage, or use the average listed in the description. On your turn; you can take a lair action to cause one of the following effects; 

• Phantasm.  The caster can pass through solid walls, doors, ceilings, and floors as if the surfaces weren't there within the domain.
• Wooden Labyrinth. The caster targets any number of doors and windows that they can see, causing each one to either open or close as they wish. Closed doors can be magically locked (requiring a successful DC 20 Strength check to force open) until the caster chooses to make them unlocked, or until the caster uses this lair action again to open them.
• Invisible Passage. The caster magically turns invisible until the caster attacks or casts a spell, or until their concentration ends (as if concentrating on a spell). While invisible, the caster leaves no physical evidence of the casters passage, so the caster can be tracked only by magic. Any equipment the caster wears or carries is invisible with them.
• Illusory Appearance. The caster covers themselves and anything they are wearing or carrying with a magical illusion that makes them look like another creature of the casters general size and humanoid shape. The illusion ends if the caster takes a bonus action to end it or if the caster dies. The changes wrought by this effect fail to hold up to physical inspection. For example, the caster could appear to have smooth skin, but someone touching them would feel potentially rough flesh. Otherwise, a creature must take an action to visually inspect the illusion and succeed on a DC 20 Intelligence (Investigation) check to discern that the caster is disguised.
• Echo. The caster creates an illusory duplicate of themselves, which appears in its own space. As long as the caster can see their duplicate, the caster can move it a distance equal to their walking speed as well as make the illusion speak on their turn (no action required). The illusion has the same statistics as the caster but can't take actions or reactions. It can interact with its environment and even pick up and hold real objects. The illusion seems real in every way but disappears if it takes any amount of damage. Otherwise, it lasts until the caster dismisses it (no action required) or can no longer see it. If the caster uses this lair action to create a new duplicate, the previous one vanishes, dropping any real objects in its possession.
• Ink Cloud. The caster fills up to four 10-foot cubes of space filled with water and ink. The inky areas are heavily obscured for 1 minute, although a steady, strong underwater current disperses the ink on initiative count 10. The caster ignores the obscuring effect of the ink.
• Foul Clone. The caster chooses one humanoid within the lair and instantly creates a simulacrum of that creature (as if created with the simulacrum spell). This hideous simulacrum is formed out of seaweed, slime, half-eaten fish, and other garbage, but still generally resembles the creature it is imitating. This simulacrum obeys the caster's commands and is destroyed on initiative count 20 on the next round.
• Prison Realm. One creature the caster can see within 120 feet of them must succeed on a DC 15 Charisma saving throw or be banished to a prison demiplane. To escape, the creature must use its action to make a Charisma check contested by the caster's. If the creature wins, it escapes the demiplane. Otherwise, the effect ends on initiative count 20 on the next round. When the effect ends, the creature reappears in the space it left or in the nearest unoccupied space if that one is occupied.
• Gravity Chaos. The caster targets up to three creatures that they can see within 60 feet of them. Each target must succeed on a DC 15 Constitution saving throw or be flung up to 30 feet through the air. A creature that strikes a solid object or is released in midair takes 1d12 bludgeoning damage for every 10 feet moved or fallen.
• Noxious Veil. The caster creates a thick cloud of caustic black smoke that fills a 20-foot-radius sphere centered on a point they can see within 120 feet them. The cloud lasts until initiative count 20 on the next round. Creatures and objects in or behind the smoke are heavily obscured. A creature that enters the cloud for the first time on a turn or starts its turn there takes 16 (4d8) acid damage.
• Dream Eater. When an unconscious creature the caster can see within 30 feet of them regains consciousness, the caster can force the creature to make a DC 15 Wisdom saving throw. Unless the save succeeds, the creature takes 16 (3d12) psychic damage, and the caster regains hit points equal to the amount of damage taken.
• Blizzard. The caster creates a blizzard in a 40-foot-high, 20-foot radius cylinder centered on a point they can see within 120 feet of them. The blizzard lightly obscures every creature and object in the area for the duration. A creature that enters the blizzard for the first time on a turn or starts its turn there is blinded until initiative count 20 on the next round.
• Maddening Feast. The caster projects an illusion and appears to feast on the corpse of one enemy within 5 feet of them that died within the past minute. Each creature of the caster's choice that is within 60 feet of them and able to see the caster must succeed on a DC 15 Wisdom saving throw or be frightened of the caster for 1 minute. While frightened in this way, a creature is incapacitated, can't understand what others say, can't read, and speaks only in gibberish; the DM controls the creature's movement, which is erratic. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to the caster's Maddening Feast for the next 24 hours.
• Beastspeaker. Beasts that have an Intelligence score of 3 or lower are charmed by the caster and directed to be aggressive toward intruders in the area.
• Summon Swarms of Pests. Summons 1d4 swarms of insects, toads, pigeons or rats. A summoned swarm appears in an unoccupied space within 60 feet of the caster and acts as their ally. It remains until it dies or until the caster dismisses it as an action.
  

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  This spell was created by the magi of wonder and whimsy; Cameron the Clairvoyant. He loved to create, and was inspired by many things around him - people, places, things, concepts, nature, anime, pop culture - and loved to craft superior unique things for the Dungeons and Dragons community. Check out his homebrew creations in every category on D&DBeyond, and feel free to incorporate them into your homebrew campaigns. Cameron the Clairvoyant is a former player-character that reached level 20 and now functions as a NPC Archwizard, and has created numerous impactful magic items, weapons, subclasses, monsters, creatures, feats and spells. Seek him out in your next quest! He loves to take requests and interact with parties of player-adventurers.