Larian Studios Forums Divinity - Original Sin Divinity - Original Sin - Enhanced Edition Differences between explorer and classical mode

Also, from the D:OS EE Wiki:

Explorer Mode
- The player gets +80% HP & +30% boost to Chances to Hit.
- NPCs get -50% HP & -25% penalty to Chances to Hit.
- Regular creatures don't have any crowd control spells (Charm, Mute, Freeze, Petrify etc.): only bosses have them.

Classic Mode
- The player gets +15% HP.
- Creatures have all of their regular spells.