Larian Studios Forums Divinity - Original Sin Divinity Original Sin - Help/Tips/Tricks Hit chance(?)

Depends on what? My warrior in late game had almost 100% hit all the time, when my melee rogue on very last boss missed every time (both in face and in the back)

hit chance is mainly determined by your main stat (Strength for warrior, Dexterity for Rogue (and Perception if you're a marksman).

Rogues tend to level their Perception a lot since people use them to detect traps etc, and that ends up cutting into your Dexterity and your hit chance. However, if you want you can make your rogue 'heartless' (personality trait), which gives +20% to hit on backstabs. Bless is also helpful.

I've used a 2H warrior/mage hybrid and a rogue archer, and during the final fight my Warrior only had 30% chance to hit the boss (60% with bless), and my marksman had a slightly higher chance to hit.

Which I think is okay. It's the final boss, it shouldn't be so easy to hit. If it was 100% I would have killed him very quickly (a 2H giant weapon with 7 Tenebrium skill and +100% damage boost from buffs would pretty much obliterate it if I used Flurry) and that would have been disappointing.