A level 10 whether it is multiclassed or not will outshine a level 5. Comparing a level 10 multiclass vs a single class leve 10 it will usually go to the single class. This all depends upon the multiclass choices and the edition being used. In general for most editions if you are a full spell caster and you multi class into a non spell caster then you are handicapping yourself. Magic is that good and you will be getting less spells and higher level spells later. It's fun for roleplay reasons but it hurts the strength of the character.
5e really makes multiclassing worse with the change to upgrade attributes every four levels of the same class taken, not total levels. 3.5 multiclass is the way to go many times if you plan it well. The statement about the full caster class remains though.
Edited: Kyrroeth on 22nd Apr, 2017 - 2:32am
With multi-classing you are giving yourself a handicap as you are not as powerful as others of your same experience. While some multi class characters do make sense it is still a hamper to the character.
Yes, I agree with Kyrroeth regarding casters… multi-classing is not a good option for them. This is especially so in 3.5 where casters are so powerful at upper levels. For other characters I've found that taking a few levels of fighter isn't a bad idea if you plan them right. This also provides you with two feats.
Generally speaking, that choice is versatility vs power.
Versatility can beat power if it combines well, such as a ranged class multiclassing with a sneaky class to do sneak attacks from afar.
But as a general rule of thumb, I have to give the effectiveness award to single classed builds, and most of the exceptions are mostly single classed, with a brief dip into other classes.
Now, that stated, multiclass characters can be a heck of a lot of fun.
Edited: daishain on 22nd Apr, 2017 - 2:50am
Multiclassing is great fun. It does add versatility to your character. I usually regret it when I do though. I'll look at what I could have been capable of if I stayed single class. I think the key to multiclassing is to have just two or three levels in the secondary class. A level 20 that has 10 levels in two classes is just terrible.
Indeed, one of the strongest characters I ever played in 5E was a multiclass. But the second class was only for 1 level. First level was a knowledge domain cleric for the basic divine spells, medium armor, two extra knowledge skills, expertise in said two skills. The rest was all Diviner Wizard.
He was only one level behind for wizard spells, pretty much could never be surprised, knew intimate details about just about everything, etc. And Doing it all while rocking an AC of 19 before enchantments.(Half plate and shield, with arcane focus in main hand rather than a weapon)
Frankly, I'd have felt guilty about his strength, were he not working with only one other person in the party. Kind of had a lot of shoes to fill.
But the mix would not have been nearly as potent if I had kept bumping cleric up as often as wizard.
That is a very powerful character Daishain but I see that both classes are full casters. You still retain the same total of spell slots.
Another consideration in 5e is the class capstone. Some of them are so powerful at level 20 that you are making a huge sacrifice to give it up. If the game goes to level 20 it is a huge sacrifice to multi class away from the Druid class. A level 20 Druid is probably the most powerful class in all of Dungeons & Dragons and is basically unkillable.
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Edited: Kyrroeth on 22nd Apr, 2017 - 1:21pm