I believe what CandleReaper means by spells are the little things that we can do outside of combat, and in combat for the magic based units, such as the Witch and the Necormancer. I don't think Candle nor I have correctly stated the card skills actually purpose. Allow me:
In the game's combat, you have a meter, and have two modes; Passive and Agreesive. If you go Passive mode, then the meter fills, but your attack drops, as if you are 'charging'. Going Agrresive will increase your attack and turn your damage into your element attack, but the meter drains. If you go Passive to the point were the meter completely fills, then you can unlease the card skill. There are two types of Card Skills, in the method that they are unleased.
The hold and drain type, like Shield Barrier, work in that you hold a button, and the skill lasts as long as you hold the button. However, your meter drops as you do this, and the skill automaticly ends when it empties. You can stop at any point, and as long as you have some meter left, you kepp that. I say that we treat the meter like energy, going Agreesive tires you out, but you do more damage and you use your element. Going Passive, you recover energy, but aren't as strong.
The charge and break, like Necro Gate, work that you hold down a button again, and charge a break gauge. When it fills, you release the button, and unleash the skill. Afterwards, you lose all of your meter. This, you charge the skill, but an enemy can attack you with a powerful blow, and stun you. You stop charging, and have to resume from the begining charging the skill. Either way, Card Skills are more like large spells that come from the cards that we all have. We can't use them on demand, just in combat. Outside of combat, you can use your characters abilities, such as spells or your Elements, normally.
Would this be alrght, CandleReaper? Sorry i kinda just took control for a second...