This is a minmax build that revolves are dealing a lot of damage from a safe distance while maintaining versatility at the same time. I’m using the 27 point buy system, and including feats and multiclassing. This build uses mostly the PHB but does contain the shadow magic subclass and elven accuracy feat from XGtE. This choice of subclass is recommended, but not mandatory, so if you wish you can choose a different subclass so that you can use material from another build. Also, you should always take the average hit points. The spells you prepare/take as a warlock and sorcerer are up to personal preference, just make sure to take the spells that the guide tells you to.
27 point buy system
This is where the minmaxing starts. You should lay out your stats as such:
STR – 8
Dex – 12
Con – 15
Int – 10
Wis – 13
Cha – 14
When you choose your race, you should definitely choose half-elf. Change your stats to:
STR – 8
Dex – 12
Con – 16
Int – 10
Wis – 14
Cha – 16
You can choose any two skills and language of your choice.
Your first level should be in Fighter. Why? This gives you proficiency in all armor and weapons (but we’re really interested in the armor here). You may now equip heavy armor and a shield. It also doesn’t matter which fighting style you take, but I recommend taking the defense fighting style because it gives you +1 AC and nothing else is useful to you.
Background really doesn’t matter for this build.
For level 2 you want to take a level in warlock. This gives you access to the famous eldritch blast cantrip. Choose Fiend as your patron. You now get 4 temporary hit points when you kill an enemy. This increases as you gain levels. You also should take hex.
For level 3, you should take a second level in warlock, which gives you two invocations. Take Agonizing blast and Repelling blast.
For level 4, you should take a second level in fighter, which gives you action surge.
For level 5, you should take a first level in sorcerer. Choose shadow magic, which gives you strength of the grave. This selection is not mandatory. Your eldritch blast now launches two beams.
Take a second level in sorcerer. You now have a decent ability called font of magic.
Take a third level in sorcerer. This is where things get interesting. You should take quicken and twin as your metamagic spells. During combat you can now cast hex, then twin, then action surge and twin again.
Take a fourth level in sorcerer. You should increase your Charisma to 18. Now during combat you can cast hex, then twin, then action surge then twin again and quicken. You deal 6d10 + 12 + 6d6 to creature A, and 4d10 + 4d6 + 8 to creature B, which is more than your party members can deal.
Take a level in rogue. Choose stealth as your proficiency if you don’t already have it.
Take a second level in rogue. Choose stealth and one of your choice for expertise.
Take a third level in rogue. Choose the assassin archetype. You now have the benefit of autocriticals. Your eldritch blast now deals 3d10. You can now deal 18d10 + 12 + 18d6 to surprised creature A and 12d10 + 8 + 12d6 to surprised creature B, which is definitely more than your teammates can deal.
Take another level in sorcerer. You now have access to 3rd level spells. Choose fireball and fly.
Take a sixth level in sorcerer. You get a decent ability (depending on the subclass you chose), and access to more spells. It really doesn’t matter which spells you choose.
Take a 7th level in sorcerer. You now have access to 4th level spells, which can be any of your choice, however I recommend taking greater invisibility.
Take an 8th level in sorcerer. Take the elven accuracy feat. You now have “double advantage” on attack rolls.
Take a 9th level in sorcerer. You now have access to 5th level spells, specifically animate objects and cone of cold.
Take a 10th level in sorcerer. Your eldritch blast now does 4d10 + 16. You now cast hunter’s mark on creature A. Then twin twice and quicken once. You deal 24d10 + 48 + 24d6 to creature A, which is 264 damage on average, and 16d10 + 32 + 16d6 to creature B which is 176 damage on average. None of your party members can deal this damage.
Take a 3rd level in warlock. Choose whichever pact you want.
Take a 4th level in warlock. Choose spell sniper.
Take a 5th level in warlock. Choose eldritch spear. You can now shoot people with eldritch blast from 600 ft away, and ignore all but full cover, meaning that you will always surprise them and get that autocritical.