Unarmored Defense
PHB p76
Beginning at 1st level, while you are wearing no armor and not wielding a shield, your AC equals 10 + your Dexterity modifier + your Wisdom modifier.

Martial Arts
PHB p76
Your practice of martial arts gives you mastery of combat styles that use unarmed strikes and monk weapons, which are shortswords and any simple melee weapons that don't have the two-handed or heavy property.

You gain the following benefits while you are unarmed or wielding only monk weapons and you aren't wearing armor or wielding a shield.

You can use Dexterity instead of Strength for the attack and damage rolls of your unarmed strikes and monk weapons.
You can roll a d4 in place of the normal damage of your unarmed strike or monk weapon. This die changes as you gain monk levels, as shown in the Martial Arts column of the Monk table.
When you use the Attack action with an unarmed strike or a monk weapon on your turn, you can make one unarmed strike as a bonus action. For example, if you take the Attack action and attack with a quarterstaff, you can also make an unarmed strike as a bonus action, assuming you haven't already taken a bonus action this turn.
Certain monasteries use specialized forms of the monk weapons. For example, you might use a club that is two lengths of wood connected by a short chain (called a nunchaku) or a sickle with a shorter, straighter blade (called a kama).

Ki
PHB p76
Starting at 2nd level, your training allows you to harness the mystic energy of ki. Your access to this energy is represented by a number of ki points. Your monk level determines the number of points you have, as shown in the Ki Points column of the Monk table.

You can spend these points to fuel various ki features. You start knowing three such features: Flurry of Blows, Patient Defense, and Step of the Wind. You learn more ki features as you gain levels in this class.

When you spend a ki point, it is unavailable until you finish a short or long rest, at the end of which you draw all of your expended ki back into yourself. You must spend at least 30 minutes of the rest meditating to regain your ki points.

Some of your ki features require your target to make a saving throw to resist the feature's effects. The saving throw DC is calculated as follows:

Ki save DC = 8 + your proficiency bonus + your Wisdom modifier
Flurry of Blows. Immediately after you take the Attack action on your turn, you can spend 1 ki point to make two unarmed strikes as a bonus action.
Patient Defense. You can spend 1 ki point to take the Dodge action as a bonus action on your turn.
Step of the Wind. You can spend 1 ki point to take the Disengage or Dash action as a bonus action on your turn, and your jump distance is doubled for the turn.
Dedicated Weapon
TCE p48
2nd-level monk optional feature

You train yourself to use a variety of weapons as monk weapons, not just simple melee weapons and shortswords. Whenever you finish a short or long rest, you can touch one weapon, focus your ki on it, and then count that weapon as a monk weapon until you use this feature again.

The chosen weapon must meet these criteria:

The weapon must be a simple or martial weapon.
You must be proficient with it.
It must lack the heavy and special properties.
Unarmored Movement
PHB p76
Starting at 2nd level, your speed increases by 10 feet while you are not wearing armor or wielding a shield. This bonus increases when you reach certain monk levels, as shown in the Monk table.

At 9th level, you gain the ability to move along vertical surfaces and across liquids on your turn without falling during the move.

Deflect Missiles
PHB p76
Starting at 3rd level, you can use your reaction to deflect or catch the missile when you are hit by a ranged weapon attack. When you do so, the damage you take from the attack is reduced by 1d10 + your Dexterity modifier + your monk level.

If you reduce the damage to 0, you can catch the missile if it is small enough for you to hold in one hand and you have at least one hand free. If you catch a missile in this way, you can spend 1 ki point to make a ranged attack (range 20/60 feet) with the weapon or piece of ammunition you just caught, as part of the same reaction. You make this attack with proficiency, regardless of your weapon proficiencies, and the missile counts as a monk weapon for the attack.

Monastic Tradition
PHB p76
When you reach 3rd level, you commit yourself to a monastic tradition, chosen from the list of available traditions. Your tradition grants you features at 3rd level and again at 6th, 11th, and 17th level.

Way of the Drunken Master
XGE p33
The Way of the Drunken Master teaches its students to move with the jerky, unpredictable movements of a drunkard. A drunken master sways, tottering on unsteady feet, to present what seems like an incompetent combatant who proves frustrating to engage. The drunken master's erratic stumbles conceal a carefully executed dance of blocks, parries, advances, attacks, and retreats.

A drunken master often enjoys playing the fool to bring gladness to the despondent or to demonstrate humility to the arrogant, but when battle is joined, the drunken master can be a maddening, masterful foe.

Bonus Proficiencies
XGE p33
When you choose this tradition at 3rd level, you gain proficiency in the Performance skill if you don't already have it. Your martial arts technique mixes combat training with the precision of a dancer and the antics of a jester. You also gain proficiency with brewer's supplies if you don't already have it.

Drunken Technique
XGE p33
At 3rd level, you learn how to twist and turn quickly as part of your Flurry of Blows. Whenever you use Flurry of Blows, you gain the benefit of the Disengage action, and your walking speed increases by 10 feet until the end of the current turn.

Ki-Fueled Attack
TCE p48
3rd-level monk optional feature

If you spend 1 ki point or more as part of your action on your turn, you can make one attack with an unarmed strike or a monk weapon as a bonus action before the end of the turn.

Ability Score Improvement
PHB p76
When you reach 4th level, you can increase one ability score of your choice by 2, or you can increase two ability scores of your choice by 1. As normal, you can't increase an ability score above 20 using this feature.

If your DM allows the use of feats, you may instead take a feat.

Slow Fall
PHB p76
Beginning at 4th level, you can use your reaction when you fall to reduce any falling damage you take by an amount equal to five times your monk level.

Quickened Healing
TCE p48
4th-level monk optional feature

As an action, you can spend 2 ki points and roll a Martial Arts die. You regain a number of hit points equal to the number rolled plus your proficiency bonus.

Extra Attack
PHB p76
Beginning at 5th level, you can attack twice, instead of once, whenever you take the Attack action on your turn.

Stunning Strike
PHB p76
Starting at 5th level, you can interfere with the flow of ki in an opponent's body. When you hit another creature with a melee weapon attack, you can spend 1 ki point to attempt a stunning strike. The target must succeed on a Constitution saving throw or be stunned until the end of your next turn.

Focused Aim
TCE p48
5th-level monk optional feature

When you miss with an attack roll, you can spend 1 to 3 ki points to increase your attack roll by 2 for each of these ki points you spend, potentially turning the miss into a hit.

Ki-Empowered Strikes
PHB p76
Starting at 6th level, your unarmed strikes count as magical for the purpose of overcoming resistance and immunity to nonmagical attacks and damage.

Monastic Tradition feature
PHB p76
At 6th level, you gain one feature granted by your Monastic Tradition.

Tipsy Sway
XGE p33
Starting at 6th level, you can move in sudden, swaying ways. You gain the following benefits.

Leap to Your Feet. When you're prone, you can stand up by spending 5 feet of movement, rather than half your speed.
Redirect Attack. When a creature misses you with a melee attack roll, you can spend 1 ki point as a reaction to cause that attack to hit one creature of your choice, other than the attacker, that you can see within 5 feet of you.
Evasion
PHB p76
At 7th level, your instinctive agility lets you dodge out of the way of certain area effects, such as a blue dragon's lightning breath or a fireball spell. When you are subjected to an effect that allows you to make a Dexterity saving throw to take only half damage, you instead take no damage if you succeed on the saving throw, and only half damage if you fail.

Stillness of Mind
PHB p76
Starting at 7th level, you can use your action to end one effect on yourself that is causing you to be charmed or frightened.

Ability Score Improvement
PHB p76
When you reach 8th level, you can increase one ability score of your choice by 2, or you can increase two ability scores of your choice by 1. As normal, you can't increase an ability score above 20 using this feature.

If your DM allows the use of feats, you may instead take a feat.

Unarmored Movement improvement
PHB p76
At 9th level, you gain the ability to move along vertical surfaces and across liquids on your turn without falling during the move.

Purity of Body
PHB p76
At 10th level, your mastery of the ki flowing through you makes you immune to disease and poison.