Another class, this one based off the Final Fantasy Dragoon for Fighters.
Different fighters choose different approaches to perfecting their fighting prowess. The martial archetype you choose to emulate reflects your approach.
Dragoons are an order of knights who focus and inherit their powers from the might of dragons. Those who seek to become dragoons focus on spears and polearms to represent the long reach of the dragon, as well as heavy armor to represent the protection of their scales.
Beginning when you choose this archetype at 3rd level, you gain access to a new action called "Jump Attack". When performing a jump attack as your action, you leap into the air to strike a devastating blow against your opponent. You may perform a Jump Attack a number of times equal to your strength modifier per long rest.
When this action is declared, you leave the battlefield. You cannot be attacked by any spells, targeted by enemies, or affected at all while performing the jump. At the beginning of your next turn, you use your Bonus Action to end your jump, landing anywhere within double your movement rate of your starting point. (Note that a full round must pass). Any target adjacent to where you land may be attacked at advantage. At 11th level, if you hit with this attack, it does double damage (and criticals reroll all those damage dice.) At 20th level, if you hit with this attack, it does triple damage.
This attack may only be performed with a spear or polearm. If you perform a Jump attack without one full round passing after landing, you gain a level of fatigue.
If you do not use your bonus action to end your jump on your turn, your reaction is used the next time the initiative count reaches 20, and you land in your original square and no attack may be made.
Starting at 7th level, you learn how to take the strength of your opponent. As an action, you may make a lancet strike. This is a single melee attack, that if it hits, restores your hit points equal to the damage dealt. You may use this a number of times equal to your Constitution Modifier per short rest.
The Dragoon gains Advantage on all Ability and Skill checks related to creatures of the Dragon type (though not attack rolls).
In addition, the Dragoon picks an energy type, Fire, Thunder, or Cold. Any opponent adjacent to where the dragoon lands takes 2d8 points of that kind of damage, unless they they succeed at a Dexterity save, against a Maneuver DC equal to 8 + Proficiency bonus + your Strength OR Dexterity modifier (Your choice). At level 20 this damage increases to 3d10
Freedom of the Sky
Now, no matter the condition of the Dragoon, He may choose to leap. This allows him an additional save at advantage against all current negative effects. If successful, those effects end and the Dragoons Jump begins. On a failure the jump fails. The Dragoon still receives any relevant saving throws at the end of the round.
The Dragoon jump ability has been mastered. As soon as the Dragoon is targeted by a melee attack or spell (not simply in the area of effect of one), she may now use her reaction to start her jump, which she may then end as a bonus action on her initiative count in combat. This causes the attack or spell to fail, as the Dragoon is no longer a valid target