Non-Fatiguing Spontaneous Magic--no die roll?

Page 81 of 5th Edition doesn't list a die roll of any kind in the formula for determining Non-Fatiguing Spontaneous Magic. Fatiguing magic requires a Stress Die. Formulaic and Ritual require a regular die roll. Doesn't seem right that Non-Fatiguing Spontaneous Magic wouldn't require a die roll of any kind. Is this a typo? If so is it Stress die or a non-Stress die? Or is it situational?

This is not a typo. There is no die roll for Non-Fatiguing Spontaneous Magic.

Non-Fatiguing Spontaneous Magic can only cast low level spells under the best of conditions. It allows the magus to cast these low level spells without the possibility of the botch. Very nice so you don't have to memorize every low level spell in the book AND it eliminates a hell of a lot of stress rolls (read --> botch dice), so the magus doesn't hit Final twilight by age 32.

Also, since the penetration is going to be really low by default, this casting type rarely effects game play.

Finally, since there is no roll, there are no botch dice addition in an unfavorable aura. The aura WILL effect the casting total, however.

So there's no chance of failure when attempting minor magic? That's kinda cool. I haven't played Ars yet, but have all the 3rd of 4th edition books. Maybe I got the idea from one of them. Regardless, I think my players will be pleased to learn that.

Yes, it's a little neat feature of 5th edition. Some flaws, however, make you roll a die just to check for botches even when not fatiguing.

If you do cast non-fatiguing spontaneous magic, you still have to roll a stress die if there are dangerous conditions, just to see if you botch. (your casting total is not affected)
So normally no roll, in combat you roll to check for botches.

Serfs Parma: I believe it also works like this for formulaic spells: normal die in many situations, stress die in stressed situations.

Not in the RAW.

This is correct, however.