The Mimic

In this world of heroes and monsters, there is one creature that has taken the idea of camouflage to a whole new level, the mimic. Whether through bloodline, experimentation, or magic, you have learned to sculpt your flesh just as they do. Your form shifts at your whim. You can do more than hide. You can melt into the environment around you to get the drop on any would be adventurers or creatures that stand in your way.

False Appearance

At 3rd level, you have unlocked your inner mimic. When you roll initiative or as an action, you can polymorph into a medium or small sized innanimate objecct that you have seen before. While in this form, your stats remain the same. You can make weapon attacks as normal, with your weapons being incorporated into your form, appearing as teeth, psuedopods, or spines, etc.

While polymorphed, you gain the following features: 

• While you remain motionless, you are indistinguishable from an ordinary object.
• Your speed is halved.
• You have advantage on the first weapon attack you make while transformed.
• You can choose to have your sneak attack deal acid damage.

You can shift back to your normal form with an action or a bonus action. You can use this feature a number of times per day equal to your proficiency bonus and can remain polymorphed for a number of hours equal to half your rogue level rounded down. Maintaining your polymorphed form requires concentration as if concentrating on a spell.

Membranous Secretions

At 3rd level, your skin begins to secrete adhesive slime. You gain a climb speed equal to half your movement speed. Additionally you gain the ability to move up, down, and across vertical surfaces and upside down along ceilings, while leaving its hands free.

Improved False Appearance

At 9th level, you have learned to push your body's limits further while changing. When you use your False Appearance ability, you can now replicate a large or tiny object.

In addition, you gain immunity to acid damage.

Defensive Budding

Starting at 13th level, when use your false appearance feature, you can summon a copy of the inanimate object you mimic. It appears in the nearest available space within 5 ft. of you. Your copy has AC 10+ your proficiency bonus, 1 hit point, and immunity to all conditions. If it has to make a saving throw, it uses your saving throw bonus for the roll. It is the same size as you, and it occupies its space.
Any time you are targeted by an attack while you remain next to the copy, roll a d20. On an 11 or higher, the attack targets the copy instead of you. The copy remains until it is destroyed, or you shift back into your normal form.

Mimic Colony

At 17th level, you feel yourself becoming part of something bigger.
You can cast the spell animate objects, with the following changes:

• Maintaining the effects does not require concentration.
• It doesn't count as magic or a spell for the purposes of counter spell, dispel magic, or anti-magic effects, etc.
• You can choose to sneak attack through the animated objects instead of yourself.

Once you use this feature, you can't use it again until you finish a long rest or you choose to expend two use of your False Appearance feature to use it again.