Running out of Mana can be a very common occurence, so having something that will refill even a little every time you crash an immobilized enemy is of great use. In effect, you're getting a partial ...

Time Bargain is great for keeping enemies frozen for longer, so if you plan on making Immobilize a core of your play style, it's well worth the extra Mana cost. Combining this with Spirit Shards can ...