Hard as Stone

At 3rd level, you learn the nature of stone to be hard and unforgiving. When you use your patient defense feature, you may enter an earthen stance, which lasts until the start of your next turn. When you are targeted by a melee weapon attack while in this stance, you may use your reaction to make a single melee weapon attack, targeting the creature that triggered this reaction, as long as it is within your reach. You must resolve the triggering attack before you make this reaction.

Steady as Stone

At 6th level, you're posture is unshakable as the earth beneath your feet. When you are forced to make a saving throw or ability check against being moved against your will, you may spend one ki point, and may remain in your space, regardless of whether you succeed or fail.

Solid As Stone

At 11th level, you begin to understand the path of still and unyielding stone. If you do not move on your turn, you gain resistance to bludgeoning, piercing, and slashing damage until the start of your next turn.

Unbreakable

At 17th level, you can learn to channel the earth beneath your feet, and call upon it for strength. At the end of your turn, you may spend 2 ki points to spend any remaining movement available to you and remain in your current space to gain temporary hitpoints equal to your remaining movement speed divided by 5*2. These temporary hitpoints last until you move willingly.

Variant Class Features.

While these variant class features are quite thematic on monks of this path, they are widely applicable to any monk you choose, and likewise are not required of monks of this path either.