The Mimic

Well, you asked for a mimic, so heres an extra dimensional mimic who lets you store your familiars inside it, so long as you feed it. 

Expanded Spell List

The Mimic lets you choose from an expanded list of spells when you learn a warlock spell. The following spells are added to the warlock spell list for you.

The Mimic Expanded Spells

Spell Level	Spells
1st	Disguise Self, Command
2nd	Arcanist's Magic Aura, Magic Mouth
3rd	Meld Into Stone, Conjure Animals
4th	Secret Chest, Giant Insect
5th	Animate Objects, Seeming

Mimic Mimic

Starting at 1st level, your patrol gifts you a miniature version of themselves to carry around. It can be used as your spellcasting focus for your Warlock spells. It is considered a tiny object. You decide what it looks like, but the following are recommended: 

• Chest
• Suitcase
• Bag
• Box
• Book
• Barrel

As an action, while touching your mimic, you can magically vanish and enter your mimic, which remains in the space you left. The interior of the mimic is an extradimensional space in the shape of a 20-foot cube, 20 feet high, and resembles your mimic. The interior is appointed with whatever decorations and furniture you like and is a comfortable temperature. While inside, you can hear the area around your mimic as if you were in its space. If the mimic is opened while you are inside, anyone looking inside sees a purple tongue and mouth and a bottomless pit. If anything is placed inside the mimic from the outside, you choose wether it appears in a similar item inside your mimics dimension, or if it stays in the outside mimics container. You can remain inside the mimic up to a number of hours equal to twice your proficiency bonus. You exit the mimic early if you use a bonus action to leave, if you die, or if the mimic is destroyed. When you exit the mimic, you appear in the unoccupied space closest to it. Any objects left in the vessel remain there until carried out, and if the vessel is destroyed, every object stored there harmlessly appears in the unoccupied spaces closest to the vessel’s former space. Once you enter the vessel, you can’t enter again until you finish a long rest. If you use the Find Familiar spell, every familiar you can create lives inside your mimic while not acting as your active familiar. 

The mimics AC equals your spell save DC. Its hit points equal your warlock level plus your proficiency bonus. 

If the mimic is destroyed or you lose it, you can perform a 1-hour ceremony to receive a replacement from your patron. This ceremony can be performed during a short or long rest, and the previous mimic is destroyed if it still exists. The mimic vanishes in a spurt of slimy purple goo when you die. 

Mimic Magic

Starting at 6th level, your mimic can help you cast spells, but at a cost. Once per long rest, you can feed your mimic at least half a dead creature's remains while attempting to cast a spell that requires material components that have a gold value. The amount of gold it can replace is equal to 20 gold worth of material times the CR of the creature. A few examples: 

• The mimic can eat two or more dead wolf remains to cast the spell Magic Mouth. 
• To cast a spell like Magic Circle requiring 100gp worth of material, your mimic could eat
  • five or more dire wolf remains
  • one or more giant crocodile remains

Spells like Secret Chest or Plane Shift that require spell components for specific multi use features in the spell cannot be replaced with this feature. You would still need a duplicate chest or a tuning fork from a specific dimension that the mimic could not create or replicate. 

Mimic Mansion

When you enter your Mimic via the Mimic Mimic feature, you can now choose up to five willing creatures that you can see within 30 feet of you, and the chosen creatures are drawn into the mimic with you.

As a bonus action, you can eject any number of creatures from the mimic, and everyone is ejected if you leave or die or if the mimic is destroyed. In addition, anyone (including you) who remains within the vessel for at least 10 minutes gains the benefit of finishing a short rest, and anyone can add your proficiency bonus to the number of hit points they regain if they spend any Hit Dice as part of a short rest there.

Mimic Murder

Starting at 14th level, your mimic now fights along side you.

Once per long rest, you can have your mimic grow and become a combat ally. As an action, the mimic can grow to fit the Mimic stat block. It fights right after your initiative and follows your every command even if you cannot give commands as your patron's magic knows your intents. It regains its hit points after a long rest and can spend Hit Die's on short rests. If it drops to 0 hit points, it shrinks back to your tiny mimic undamaged. You can still use the Mimic Mimic feature while your Mimic is in Mimic Murder mode. It can travel while you are in Mimic Mimic mode and will still take orders from you while you are inside your mimic.