QUOTE(abc12345678901 @ Jan 25 2017, 10:41)

er isn't 50 hath like 250k credits or so (IMG:[
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style_emoticons/default/blink.gif) and drains mana? seems horribly non cost efficient unless I'm missing something. Also doing dark mage atm (yes i know, not good idea, but I like spamming magic (IMG:[
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style_emoticons/default/sad.gif) ) so not sure how that effects scroll choices.
I don't have any mana issues with IA3 and my Power 2H, which is basically the highest mana consumption playstyle. At worst I have mana draughts on 90% of the time. Since I tasted IA, I consider myself stupid for not using it earlier.
There are a few other advantages to Innate Arcana:
1) You only spend the good amount of mana for the duration of the combat, which means you do not waste mana casting a buff that will only last 4-5 rounds. It's especially useful when you do a RE.
2) You do can cast the spell anyway, while the IA buff is active, to then have the regular buff. It can be very handy when you really need a Channeling to proc.
3) You just stop worrying about a good amount of your buffs, which guarantees faster rounds and a safer combat situation
4) Overall it allows playing in higher difficulties in a much safer way.
There do are inconvenients though:
1) The upkeep cost is calculated to be equal to a normal cast. It means that you cannot use spirit stance for reduced costs for spell casts.
2) The upkept spells don't trigger Channeling.
3) Going below 10% MP is extremely dangerous, as everything just expires all of a sudden. You'd better not get hit very hard at such a moment.
But overall, it's very handy. Your mana will still keep going up despite the upkeep cost if you have a mana draught on. And even when it's not on, your mana bar depletes very slowly.