Larian Studios Forums Beyond Divinity (English) Help/Tips/Tricks extra duration are for what spells ?

In the Battlefield of Act 2 a merchant is offering weather magic extra duration-skill. Since i love using lightning storm, i wonder if extra duration makes my lighting storm then take longer, making one round damage more ?

Actually, for other shaman skills it increases the duration, but with Lightning Storm it increases the damage.

Thank you..but what about the storm hammer spell ? It was suggested several times here to have, and it looks like its AoE also..is it useful to have when someone has lighting storm already ? And does it take advantage from "extra duration" too ?

You've probably figured this out by now, but Hammer is quite effective. It is primarily a single target spell, but does have an area effect, as well. Extra Duration only affects weather magic.