Which spells do folks consider worth learning or upgrading ?

[skel1977]

So far im doing 2 demon summonings at beginning of battle. Or 2 ice snakes at beginning of battle depending.
After the first turn the demons are the ones taking beatings so im heavily ranged based now.

Also berserk, mass bless, mass haste, mass weakness are all worth learning as well but its hard to get everything since runes can be hard to get and mana as well. You have to pick and choose and base a strategy around your guy.