Blademaster

Rather than focusing on raw physical power and force of will, the Blademaster instead focuses on an enemy's weak spots, and placing their blade where it is most deadly.

Level 3: Improved Critical

Your attack rolls with melee weapons can now score a Critical Hit on a roll of 19–20 on the d20.

Level 3: Killing Blow

Your training makes even the slightest flaw in an enemy's defenses a death warrant.

When you crit with a melee weapon, you add your weapon's maximum possible damage to the damage roll, adding any damage modifiers after. For example, scoring a critical hit for a longsword would deal 1d8 + 8 + your Strength modifier.

In addition, immediately after you score a Critical Hit, you can move up to half your Speed without provoking Opportunity Attacks..

Level 10: Quick Learner

Your mind is so honed you can spot weak spots in an opponent's defenses, even while taking a a blow yourself. After being hit by a melee attack (and resolving the damage of that attack), you may use your reaction to make an attack of opportunity against the attacker with advantage. You must be weilding a melee weapon to use this feature.

Level 18: Swift End

You simply will not allow other blades to mark your body, and have taken great measures to avoid it. You gain these benefits:

• You gain +2 to your Dexterity modifier, to a maximum of 22.

Deft Dodge. You are proficient in and have Advantage on Dexterity Saving Throws, as well as advantage on Strength Saving Throws, and whenever you roll 18–20 on a these Saving Throws, you gain the benefit of rolling a 20 on it.

Punishment. When an creature makes an melee attack on you and misses, you may use a reaction to make an opportunity attack against that creature with advantage. In addition, when a creature makes an opportunity attack against you while it is within 5 feet of you, regardless of whether or not it hits(immediately after resolving the damage of the attack if it hits), you may use a bonus action to make a melee attack against that creature.