You excel at defending narrow passages, doorways, and other tight spaces. As a bonus action, you can enter a defensive stance that lasts until the start of your next turn. While in your defensive stance, you can make opportunity attacks without using your reaction, and you can use your reaction to make a melee attack against a creature that moves more than 5 feet while within your reach.

When you roll a 1 or 2 on a damage die for an attack you make with a melee weapon that you are wielding with two hands, you can reroll the die and must use the new roll. The weapon must have the two-handed or versatile property for you to gain this benefit.

When you are wielding a melee weapon in one hand and no other weapons, you gain a +2 bonus to damage rolls with that weapon.

You adopt a particular style of fighting as your specialty. Choose one of the following options. You can't take a Fighting Style more than once, even if you later get to choose again.

The Gravity Knight is a martial class that augments traditional combat techniques by manipulating gravity through a limited and systematic type of psionics. They train body and mind to fight with vigor and elegance, while relying on their unique abilities to control the battlefield.

Crushing Blow

You can empower your attacks with increased ferocity. On a successful melee strike with a weapon that deals slashing or bludgeoning damage, you can expend 1 Focus point to deal an additional 1d6 weapon damage. You can spend a total number of points equal to ½ your level to deal an additional 1d6 weapon damage per point spent. You can only deal this damage once per turn. If you spend five or more points in this way on a Large or smaller creature, the target must succeed on a Strength saving throw or be knocked prone. The DC for this save is 10 + the number of Focus points spent.

Lightness

At 2nd level, your subconscious mind has begun to learn to dissociate yourself from the force of gravity. While you are conscious, your weight, and the weight of any armor you wear, is reduced by one-quarter. The maximum Dexterity bonus of armor you are wearing is increased by 1. For example, if you are wearing heavy armor and you have a Dexterity score of 12 or higher, you may add 1 to your AC. Your sensitivity to natural gravity means that you always know which direction is up, even underwater or when otherwise disoriented. Your base walking speed is increased by 5ft.

Improved Lightness

At 7th level, as your conscious understanding of gravity continues to increase, your subconscious has also continued to improve your dissociation from the natural law of gravity. While you are conscious, you and any armor you wear weighs half as much. The maximum Dexterity bonus of any armor you are wearing is increased by 2. Additionally, your sensitivity to natural gravity as improved to the degree that you can always discern your elevation above or below sea level, to within 30ft. Your base walking speed is increased by an additional 5ft.

Extreme Lightness

At 13th level, your subconscious divorce from gravity has increased to the degree that you and any armor or clothing you wear weigh three-quarters less than usual. The maximum Dexterity bonus of any armor you are wearing is increased by 3. Your sensitivity has become great enough to feel the unique texture of the gravity around you; you always know on what plane of existence you are, even if you have never visited that plane before. Your base walking speed is increased by an additional 5ft.

Weightlessness

At 17th level, your subconscious mind can completely isolate you from the force of gravity. While you are conscious, you are effectively weightless. You can walk and run as normal, but you do not sink in water or in soft earth. You may choose to ignore this effect, the effects of your own Disciplines, or spells which change the force of gravity (such as Levitate or Reverse Gravity) at will. You no longer count against the number of allies you can isolate from the effects of your Disciplines.

Focus Pool

Your training allows you to harness the force of gravity, but it requires tremendous mental focus to accomplish. Your ability to maintain this effort is represented by Focus points. Your Gravity Knight level determines the number of points you have, as shown in the Focus Pool column of the Gravity Knight table. You can spend these points in various ways to fuel various class features. You regain all Focus points on a long rest. During a short rest, you can regain a number of points equal to your level plus your Intelligence modifier.

Disciplines

You can control gravity in specific ways through trained forms called Disciplines. Like psionics, your Gravity Disciplines are magical and function similarly to spells. While the energy for these abilities is entirely mental, they require somatic components to transmit that energy. Even if you have the ability to use somatic components with your hands full (such as with the Warcaster feat) you are still unable to use your Disciplines if you have a condition that renders you unable to move, like if you are Restrained. For Discplines with area effects, you may choose a number of creatures or objects, including yourself, equal to your proficiency bonus plus your Intelligence modifier to be unaffected. The effects of your Disciplines are always limited by your range, even if a target creature or object is within range. For example, the Tier 3 "Throw/Yank" discpline allows you to push a creature or object up to 30ft, but if the creature is already only 10ft away from the edge of your range, the creature would only be pushed back 10ft.

At 3rd level, you gain access to all Tier 1 disciplines and your range is 20ft. The DC for your disciplines is 10 + your proficiency bonus + your Intelligence modifier.

Tier 2 Disciplines

At 7th Level, you gain access to all Tier 2 disciplines. Your range increases to 30ft.

Tier 3 Disciplines

At 11th Level, you gain access to all Tier 3 disciplines. Your range increases to 40ft.

Tier 4 Disciplines

At 15th Level, you gain access to all Tier 4 disciplines. Your range is 50ft.

Ability Score Improvement

When you reach 4th level, and again at 6th, 8th, 12th, 14th, 16th and 19th 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.

Extra Attack

At 5th level you can make two weapon attacks when you take the Attack action on your turn. At 18th level, this increases to three weapon attacks.