Unhinged broken class. Don't take this seriously.  

Level 3: Swift Attack

Starting at Level 3, you may take an additional attack whenever you take the Attack action.

This benefit stacks with the Extra Attack feature at level 5 (4 attacks), 11(6 Attacks), and 20 (8 attacks) for the Fighter class only.

Level 3: Tactical Attack

Thanks to your massive IQ, you've learned to sacrifice any other options in the name of attacking again. 

On your turn you can expend your Bonus Action or Reaction, or both, to make an additional attack respectively. When rolling for damage, you do not add the modifier made to make the attack.

Level 7: Hasted Attacks

You have achieved what Wizards only dream of doing so, in the name more attacks.

As a Magic Action, you can cast the haste spell on yourself only a number of times equal to proficiency bonus. While concentrating on the spell, you have advantage on all Constitution Checks made to keep your concentration. Additionally, your attack made by utilizing Haste benefits from Swift Attack. 

You regain all expended uses on a Long Rest.

Level 10: Heroic Attacks

The thrill of attacking drives you to see fights through to the end.

Once per turn during combat, you can gain Temporary Hit Points equal to the damage dealt during one of your attacks plus your Constitution modifier (minimum of 1). These hit points do not stack with current Temporary Hit Points: you choose which to keep.

Level 15: Superior Attacks

Your need for more attacks starts to break reality. Tactical Attacks no longer consumes your Bonus Action or Reaction if you haven't used them yet this turn. 

Furthermore, when you cast Haste on yourself, it no longer requires concentration. 

Level 18: Godly Attacks

 You understand attacking better then breathing, almost to a detriment. You gain the following benefits:

-  Driven Attacks: If you miss an attack roll, all attacks for the rest of your turn are made with advantage.

-  Ambitious Critical: During attack rolls made with advantage, you can Crit on a 17-20.

- Divine Attack: On your final attack, you an choose to do an additional 1d10 Force, Radiant, or Necrotic damage for each attack made this turn. 

When using Divine Attack, roll a d100. On a 10 or less, your weapon shatters into pieces, and you take Slashing damage equal to half (round up) of your Divine Attack damage. The weapon is unsalvageable by any means besides using the Wish spell.