BG3 multiclassing lets one character combine levels from different classes, but every level spent in a second class changes what the first class reaches before the level-12 cap.
Start with one primary role
Decide what the character must do in combat or support before adding a second class. Multiclassing works best when the second class strengthens that role or adds a specific missing feature.
Ask what each class contributes
- Which features require deeper investment in the primary class?
- What exact feature are you taking from the second class?
- Does the second class add something unique or duplicate tools you already have?
- Does the split still fit the party's role coverage?
The level cap is the real cost
A 6/6 split, 8/4 split and 10/2 split do not just look different on paper—they unlock different class features. Use the Multiclass Level Planner before committing so you can see the budget clearly.
Leveling order matters
Even if two builds end at the same final split, they can feel very different while leveling. Get the features that make the build function first, then add secondary-class utility later.
Avoid multiclassing for novelty alone
If a full single-class build already covers the role well, adding another class may make the character weaker or delay important progression without solving a real problem.
Source: Larian game overview.