[RPG] Is a dual-wielding Eldritch Knight fighter workable


As I understand it an Eldritch Knight has the ability to cast a spell and attack as a Bonus Action.
Two-weapon fighting allows you to attack normally with one hand and take a Bonus Action to attack with the off-hand.

Now it seems to me that you cannot benefit from both and they are redundant abilities. Despite this I've read posts suggesting that dual wielding eldritch knights are a good combo.

My question: Is it worth it to combine both or should I stick to one — going either eldritch knight with one weapon and the dueling fighting style, or two-weapon fighting with one of the other fighter archetypes?

New to 5e but experienced in other RPGs if that matters.
I'll be playing my first game of 5e soon and I planned to play a variant human two-weapon-fighting fighter with the Dual Wielder feat using a longsword + handaxe as my starting outfit. But as the first one-shot game might lead to a campaign, I want to start out "right" and the eldritch knight sounds interesting.

Best Answer

Two-weapon fighting is itself, not worth it. Straight out of the box, using a two-handed weapon does better damage. See this question for details. By the time you add in the damage boost from the Great Weapon Master feat, a two-handed weapon crushes two-weapon fighting completely.

It ges worse for two-weapon fighting, though, because the whole benefit of two-weapon fighting is being able to attack with a bonus action in addition to your regular attacks. However, a two-handed weapon (glaive or halberd) can do that anyway, thanks to the Polearm Master feat.

For most characters, getting both these feats is a little impractical. But as a variant human, you get a feat right out of the box, and as a Fighter, you get extras along the way. So this is completely attainable.

Everything above is optimization advice. A two-handed weapon does far better damage than two-weapon fighting, but if you want to use two-weapon fighting, you should go for it.

Now, the question you really wanted to know - is attacking with your action and then with a bonus action worth it, since you can cast a spell with your action and then attack with your bonus action?

And the answer is yes, absolutely. Attacking will usually be a better use of your action than casting a spell. For example, at level 13, you could cast fireball for 8d6 damage, averaging 28 damage. However, if you instead attacked with your action, you could attack 3 times, dealing 1d10 + 15 damage each time - for an average of 61.5 damage - more than twice as much.

This assmes that you're using the advice I gave above. If you're dual-wielding, you could attack 3 times for 1d8 + 5 damage, averaging 28.5 damage. Still better than casting fireball, but only just.

So why use spells? Well, the easiest example is casting haste on yourself, giving you an extra attack every round, as well as some other benefits. But you're likely to do that on the first round of a combat, and then spend the rest of the time attacking.