Mason's awesome Seraphim build introduced a mechanic that allows concentration spells to be cast indefinitely by manipulating the atronach stone with fortify restoration potions. This has fascinated me and I thought I'd do a little experimentation with it (and finally contribute something around here!). I need to start by saying that unfortunately I haven't completely cracked what is going on but I may be able to start a conversation that will get us a bit closer. Also there is a tl;dr at the bottom ...
The thing that set me off with this was the simple thought: why the atronach stone? Alongside the spell absorption it grants +50 magicka and as we know both components are modified by the fortify restoration effect. So I wanted to see what would happen if you used the same fortify restoration potion stack but used an item that granted +50 magicka instead of the atronach stone.
And it worked! Drinking a philter, then a draught and then a philter again and putting on any item that grants +50 magicka on a character that has only the 100 base magicka enables the unlimited concentration casting effect. I have tested this with the adept hood, a necklace of eminent magicka and nahkriin. I also tested the necromancers amulet but that didn't work - I suspect it is not affected by fortify restoration. This is tested on the PS3 by the way so if someone could test the same on the 360 and PC that would be great.
So that means that the unlimited effect has nothing to do with spell absorption and is purely to do with the amount of magicka your character ends up with. The philter, draught, philter stack gives a modifier of (((0.4*0.3)+0.3)*0.4)+0.4 = 0.568 - each potion is modified by the fortify restoration effect in place at the time of drinking. 0.568*50 = 28.4 giving the total that we see of 100+50+28.4 = 178 magicka as the game rounds decimals on the display.
I was very suspicious of that rounded off 0.4. I wanted to see if it was possible to get a different magicka value that had a 0.4 with what I had available on my test character and it turned out I could. Drinking a potion then a draught gives a modifier of (0.2*0.3)+0.3 = 0.36. Using an item of major magicka this time gives (0.36*40)+40 = 54.4. And doing this also allows the unlimited concentration casting! Other decimal values do not seem to work but I have by no means tested all combinations ...
It can't be the case that the effect is purely a result of having a magicka value that ends in 0.4. We know that the effect does not work if your base magicka before putting the item on is not 100 so in some way that is changing the equation. This is unfortunately as far as I have got and I am little limited in what I can test on the PS3. If anyone has any further ideas or finds any other combinations of potions and fortify magicka items that produce the effect please add below.
tl;dr: Unlimited concentration casting doesn't need the atronach stone and can be enabled with at least one other combination of fortify restoration effects and fortify magicka values.
Edit - List of currently known combinations of potions and fortify magicka apparel values that produce the effect (drink potions in the order given):
Philter, Draught, Philter with +50
Philter, Draught, Philter with +50 and +50
Potion, Draught with +40
Philter, Draught with +70
Philter, Draught with +50 and +20
Philter, Draught with +20
Potion, Draught with +20 and +20 - Achievable at lv10!
Interesting findings. I remember talking with Mason about this when he first found it, and I could've sworn he said he tested it with items of Fortify Magicka and couldn't get it to work, but maybe I'm mis-remembering, or maybe he didn't have any items with +50 Magicka.
In any case, it's especially curious that you were able to replicate it with the Potion --> Draught and a +40 item. You're right, that .40 Magicka can't be the only factor at play, but it sure seems like a requisite element of the equation.
We could further test by trying Philter --> Draught --> +70 Magicka item (Peerless Magicka item, or Mage's Circlet @ Level 25). I'll try to check that tomorrow if I have the time.
James mentioned that he was trying to get to the bottom of this as well, but I don't know what kind of progress he's made. I have no experience with the CK, but I may try to poke around tomorrow and see if it can shed any light on this.
Great work here, Parabola! Let's get to the bottom of this one!
Thanks Teccam. Yeah I was really hoping this would attract the attention of people with access to the creation kit. I'm just working with hunches and guesswork!
Ok the plot thickens and I'm not sure it's in a good way ... You're right - Philter, Draught, +70 should work - ((0.4*0.3)+0.3)*70 = 29.4 which will give 199.4 overall magicka. Embarrassingly my test character isn't at a level where he can get an item of peerless anything and being a hardy nord warrior sort of chap hasn't done the college questline ...
However - what about two items that add up to +70? Well I've tried an eminent (+50) and a minor (+20) and that worked! Then I tried a major (+40) and a 'of magicka' (+30) and it didn't ... Bit upset by that I'm not going to lie! I've checked whether the order you put the items on makes a difference and it doesn't - 50 and 20 works, 40 and 30 doesn't.
i need a lil help with this. what items should i be wearing and what potions would u guys reccomend me taking?
Dude, that comment is from a year and a half ago
The end of the topic lists all known item/potion combinations for the glitch. Finding the items is up to you, since loot spawns randomly.
So there is a fortify magicka value that allows unlimited casting? Any specific numbers? I believe I should be able to test those with modav command
OK, ran some tests with modav command and here is what I concluded
x.4 fortify magicka (where x<27) - doesn't work
x.4 fortify magicka (where x>27) - works!
x.y fortify magicka (where x and y are arbitrary numbers (y =/= 4)) - doesn't work
Ah - interesting info! Could you run more tests with two fortify magicka values in combination or are you limited to just changing the overall total? For the life of me I can't think of a good reason why the 50+20 worked when 30+40 didn't. I've also tried Philter, Draught, Philter and 20+30 and that didn't work either!
What potions do you use? The situation is like this?
50 + 20 + potions = x.4
30 + 40 + same potions? =/= x.4
I think number 27 is tied to the base cost of sparks spell which is 26 according to UESP
Yeah that's basically it. Have a look at the post below. The last thing I've found there is really odd because Philter, Draught, +20, +50, +50 definitely is x.4 (170.4 to be exact) regardless of how the game handles the rounding but that didn't work.
Hmm... What I do is type in, for example, player.modav magicka 99.4 and have my magicka at 199.4 (written in green in Skills menu). Just tell me what numbers to use and I'll test them
Can you modify base magicka too? Could you test to see if it becomes 17<x<117 with 110 base magicka?