Way of the Four Celestial Beasts

Monks of the Way of the Four Celestial Beasts seek perfection in the natural beasts and monsters of the world, polymorphing their limbs and bodies to in order to imitate them. They observe and study natural creatures, gleaning ways to push their bodies to ever more amazing (and sometimes, even more grotesque) forms.

Thousand Forms

You learn to channel animalistic aspects of the beasts of the world. Aspects requires you to spend ki points each time you use them. As a bonus action, you alter your physical form to gain different characteristics. When you do so, you can choose to use one or more aspects you know. Each effect has its own ki point cost. Add them together to determine the total cost, which must not exceed a cost equal to your proficiency modifier. This transformation lasts for 1 minute, until you die, or until you end it as a bonus action.

You know the two animal aspects of your choice. You learn two additional animal aspects of your choice at 6th, 11th, and 17th level.

Whenever you finish a long rest, you can also replace one animal aspect that you already know with a different aspect.

3rd Level Animal Aspects

Starting at 3rd level, you can learn the following aspects:

Bull's Horns (1 ki): You grow a pair of horns and gain the strength of an ox. You have advantage on Strength (Athletics) checks, and once per turn, when you hit a creature with an unarmed attack, you may attempt to shove it with your horns. That creature must make a Strength saving throw, or be knocked prone or pushed up to 5 feet away (your choice) from you on a failed save.

Owl's Sight (1 ki): Your vision sharpens. You gain darkvision out to a range of 60 feet. If you already have darkvision from your race (or some other source), its range increases by 30 feet. Additionally, you have advantage on Wisdom (Perception) checks that require sight.

Octopus' Grasp (1 ki): One of your limbs transforms into a tentacle, with which you can make unarmed strikes with. When you hit a creature with this tentacle, that creature is grappled if it is not more than a size larger than you. While the target is grappled, you cannot use this tentacle on another target.

Panther's Grace (1 ki): The aspect of the panther turns you into a fearsome stalker and predator. You have advantage on Dexterity (Acrobatics) and Dexterity (Stealth) checks and gain a climbing speed equal to your speed. Additionally, once per turn when you hit with a weapon attack, if you have advantage on the attack roll, you deal additional damage equal to your Martial Arts die of the weapon's damage type.

Hawk's Talons (1 ki): Your feet twist and deform into sharp talons, with which you can make unarmed strikes with. Unarmed strikes made this way deal slashing damage instead of bludgeoning, and once per turn when you make a unarmed attack with these talons against a creature, you can roll your Martial Arts die and add it to the attack roll. You can do this before or after making the attack roll, but before any effects of the attack are applied.

Fox's Guile (1 ki): Cunning and swift, you slip away at a moment's notice. Opportunity attacks made against you have disadvantage on the attack roll, and you increase your walking speed by an amount equal to half that granted by your Unarmored Movement feature.

6th Level Animal Aspects

Starting at 6th level, you can learn the following aspects:

Chameleon's Cloak (2 ki): Your skin's hue adjusts to your surroundings, allowing you to meld into the background easily. Wisdom (Perception) checks made to see you have disadvantage. and you have advantage on Dexterity (Stealth) checks. Additionally, when you take the Hide action and succeed, you become invisible until you move, attack, or cast a spell.

Eagle's Wings (2 ki): You sprout large, feathery wings. You gain a flying speed equal to your walking speed.

Leech's Bloodletting (2 ki): Your teeth combine and shift to become like a leech's, which you can make unarmed strikes with, allowing you to sap vitality from your enemies. Unarmed strikes made this way deal necrotic damage instead of bludgeoning, and when deal damage with this unarmed strike you gain temporary hit points equal to the damage dealt. Additionally, you gain a swimming speed equal to your walking speed, and can breathe water as well as air.

Spider's Skittering (2 ki): Four pairs of spider legs emerge from your back, allowing you to traverse walls and webs, and spit out webs. You can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check. You can cast the web spell as an action (requiring no material components), you ignore movement restrictions caused by webbing, and while in contact with a web, you knows the exact location of any other creature in contact with the same web.

Wolf's Savagery (2 ki): You empower yourself with the instincts of the wolf, most skilled of hunters. You have advantage on an attack roll against a creature if at least one of your allies is within 5 ft. of the creature and the ally isn't incapacitated. You have advantage on Wisdom (Perception) checks that rely on hearing or smell.

Pangolin's Scales (2 ki): Large and thick protective scales protrude and grow all over your body, protecting you from harm. While you aren't wearing armor or wielding a shield, your base AC equals 12 + your Dexterity modifier + your Wisdom modifier. Additionally, you gain short, but sharp claws, well-suited for digging. You gain a burrowing speed equal to your walking speed.

11th Level Animal Aspects

Starting at 11th level, you can learn the following aspects:

Hydra's Heads (3 ki): Two lacertilian heads, hungry and vicious, emerge from your shoulders, which you can make unarmed strikes with. When you use your Flurry of Blows, you can make up to two additional attacks with it (up to a total of four Flurry of Blows attacks), provided that each Flurry of Blows attack targets a different creature this turn.