That.
Some spells, either Arcane, Mage or Priest, seem useless or so specific that the rarelly will be used.
Have you found any of those "rarely" used spells more than "rarely"? Which one? Why?
Actually, I'm playing as a priest. There is a spell that I use a bit: Pull.
As a melee class, there are some combat situations where trying to defeat several enemies at the same time is impossible. Or there is an enemy that is firing at me from an unnacesible place for me.
In such cases, I use the Pull spell to "attrack" the enemy towards me and then kill him. I find Pull spell very useful.
Other spells that I find very useful and I use all the time are the spells Holy Water and Holy Bread, that create water and bread to drink and eat. Instead of carrying with me an extra load of food and water, I just create them when I need, so I can carry more useful things either to use or to sell.
In addition, I find the Life Water (creates a +10 HP potion) quite useful. It may seem a spell that is underpowered and useless, because it costs 20 mana to create a +10HP potion, while I can heal that same amount with just Rejuvinate Spell with less mana. Well, actually, they are different things. I use the Life Water spell when I start the map (and if I am out of these potions) to create some potions. During the quest, sometimes my mana gets really tight after hard battles, so I need mana for something else that is not healing, for example, protecting myself, curing poison, enchanting my weapon, etc... So here is where those potions are very handy, I can heal quite a bit without spending my mana. And also, I don't need to carry a lot of other potions because I can create my own when I need. Of course I carry 3 high healing potions for very harsh situations