Do you want to build some NOVA? (5e Optimized Character Build)
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To Author. I suggest looking at Master_Assassin_(5e_Optimized_Character_Build), it is trying to achieve the same goal.
As noted in the title, the point of this build is to build NOVA. The combo this build does works once per short rest. After that initial burst, you aren't bad at combat, but you aren't optimized for DPS so you won't continue to output damage at the same absurd rate.
Let’s start with your race. You’re playing a half-elf. Did you really think there was a chance you’d be playing anything else?
You need to get 15 CHA, (17 with your half-elf bonus). After that, things are sort of up to you. I’d recommend something like 14, 10, 15, 8, 8, 15 which will be 15, 10, 16, 8, 8, 17 after racial modifiers. The only thing you need for your damage is that Charisma though.
Next you’re going to take your first 4 levels in Fighter. Fighter first lets you wear full plate armor for maximum defense.
At level 1, grab that great weapon fighting for just a hint more damage. If you want you can drop that damage for some more defense, but I’d take it, you’ll be rolling quite a few D6, and this brings the expected damage on a D6 up from 3.5 to 4.1666, which is a 20% boost.
At level 3, you become a battle master. Grab Feinting Attack, Precision Attack, and Menacing Attack (you can swap this for disarming attack or tripping attack, all you need here is the damage).
At level 4 you get a feat. Snag that great weapon master feat. Now you’ve got that nice heightened damage, but it’s still pretty tough to hit with a -5 to attack roles. Let’s see if we can fix that.
At level 5, we’re swapping over to Warlock.
At level 1, you’re going to become a hexblade. (Anonymous Edit: You cannot use your CHA for attack/damage with a Greatsword) (Author's correction: If you continue reading the skill, you'll see that in XGE Hexblade you are able to use any pact weapon regardless of type with CHA for attack/damage) You can't use it on Greatsword because you can not use it on any weapon that has the two handed property. It specifically states: The influence of your patron also allows you to mystically channel your will through a particular weapon. Whenever you finish a long rest, you can touch one weapon that you are proficient with [and that lacks the two-handed property]. When you attack with that weapon, you can use your Charisma modifier, instead of Strength or Dexterity, for the attack and damage rolls. This benefit lasts until you finish a long rest. If you later gain the Pact of the Blade feature, this benefit extends to every pact weapon you conjure with that feature, no matter the weapon's type.
At level 3, you’re going to grab pact of the blade. This is necessary, because you can't get the charisma bonus on a non-conjured two-handed weapon.
At level 4, you’re going to grab elven accuracy and pop your charisma up to 18 (from Xanathar’s guide).
At level 5, you’re going to make sure you’ve got these invocations: Eldritch Smite, Thirsting Blade, and Improved Pact Weapon. (Xanathar’s guide for eldritch smite and improved pact weapon) (edit: Thirsting Blade does not stack with the fighter's 'Extra Attack' feature. See Player's Handbook Chapter 6: Multiclassing, Class Features, Extra Attack)
Now you’re ready to start fucking up anyone who gets in your way!
Start by tossing your Hexblade’s Curse onto your target. If you can’t close distance this round, that’s fine, just wait it out and start with feinting attack next round, then continue with your combo. Now that they’re cursed, go for your first attack. Once you roll, try to determine whether you just hit. If you think you’re close, toss a precision attack on there, adding a d8 to your roll. If you still miss, you’ll just try again next attack. Once you hit, pop that eldritch smite for an extra 4d8 damage that also knocks your opponent prone.
Now it gets fun. Pop your action surge, then procede to use your 3 more attacks to beat the shit out of your opponent who’s now lying on the ground. Make sure to use your great weapon master for the +10 damage. The -5 to hit doesn’t really mean much, because you get 3 rolls off of your advantage with elven accuracy. Even more, you’ve got +4 to damage from hexblade, AND you crit on a 19 or a 20, which gives you a 27% chance of critting across all 3 attacks. Oh BABY. Make sure to use your menacing attack here, just to throw in those extra superiority dice on damage. They’ll never know what hit them.
With no crits, and all hits (which is pretty likely, you’ve got a lot going for you on hitting) this does First Attack: 2d6 + 4 (CHA) + 4 (hex curse) + 4d8 (eldritch smite) 3x Remaining Attacks: 2d6 + 4 (CHA) + 4(hex curse) + 10 (great weapon master) 2 Menacing attacks: 2d8 For a total of 8d6 + 6d8 + 62 damage, not counting critical hits, which are likely. If you [do the math out] on hit and crit probabilities, you have an EXPECTED damage of over 100 in a single round until the opponent is over 19 AC. That’s a shitton of damage at level 9. Also, you’re doing this with 16 CON, and full plate armor. You one thicc, ouchy motherfucker. Also all of the abilities you need to use here recover on short rests.