Exploit: spell absorption increase your magicka when AoE yourself

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Lywzc
Posts: 107
Joined: Mon Sep 23, 2019 6:15 pm

Exploit: spell absorption increase your magicka when AoE yourself

Post by Lywzc »

Is this intended? Make a spell that has 3 cheap destruction effects, lowest magnitude and Area at Range. Get spell absorption and cast it under your feet. At first when your destruction is low your MP will slowly drain but still very effecient. However at high destruction skill this will actually increase your MP so as long as you have MP to cast it once, you can spam it to revcover your MP to full.

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Interkarma
Posts: 7236
Joined: Sun Mar 22, 2015 1:51 am

Re: Exploit: spell absorption increase your magicka when AoE yourself

Post by Interkarma »

Spell absorption from own AOE is 100% intended. It's the sorcerer way.

But not sure about your exact circumstances as described. Could you please provide a repro save for me to start from?

The expected outcome is player re-absorbs no more than the same cost required to cast spell. So there might be a gap in the calculations somewhere if that's happening.

Lywzc
Posts: 107
Joined: Mon Sep 23, 2019 6:15 pm

Re: Exploit: spell absorption increase your magicka when AoE yourself

Post by Lywzc »

This is the save file.
My theory is that since spell absorption is based on effects rather than spells, it will absorb 3 effects as 3 spells rather than 1, which means you can cast the spell for 5 MP but when absorbing it will absorb 3 spells which is 15 since the minimum cost is 5. This is confirmed since by doing this once I net gain 10 MP.
SAVE2.zip
(243.27 KiB) Downloaded 53 times

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Interkarma
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Re: Exploit: spell absorption increase your magicka when AoE yourself

Post by Interkarma »

Your intuition is correct. Because spellpoint refund is calculated per effect, it's possible to setup conditions where player can absorb more than total cost of spell.

I've added a sanity check so that self-absorb cannot refund more than the total casting cost of spell. This only applies to self-cast spells.

https://github.com/Interkarma/daggerfal ... cc2941e2cf

Lywzc
Posts: 107
Joined: Mon Sep 23, 2019 6:15 pm

Re: Exploit: spell absorption increase your magicka when AoE yourself

Post by Lywzc »

A new problem arose. After the last fix, now as long as your spell has 1 destruction effect you can absorb the whole spell making it exploitable again by making a spell that has 1 destruction and 2 other effects with Area at Range. Before you could only absorb the destruction part of it but now you can absorb all of it meaning free spell.
I suggest to first calculate the cost of destruction effects of the spell then divided by the cost of all effects then multiplied by the spell cost. So if your spell is completely destruction you will absorb all of it but if your spell is only part destruction then you will only absorb the destruction portion of it.

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Interkarma
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Joined: Sun Mar 22, 2015 1:51 am

Re: Exploit: spell absorption increase your magicka when AoE yourself

Post by Interkarma »

The change above is that total amount absorbed cannot exceed total spell cost. You're still only refunded cost of destruction effects, that hasn't changed. Only now refund is capped at spell cost so you can't absorb more than spent casting.

If you're observing something different, I'm happy to take a closer look if you can please provide a repro save.

Lywzc
Posts: 107
Joined: Mon Sep 23, 2019 6:15 pm

Re: Exploit: spell absorption increase your magicka when AoE yourself

Post by Lywzc »

Interkarma wrote: Fri May 27, 2022 5:59 pm The change above is that total amount absorbed cannot exceed total spell cost. You're still only refunded cost of destruction effects, that hasn't changed. Only now refund is capped at spell cost so you can't absorb more than spent casting.

If you're observing something different, I'm happy to take a closer look if you can please provide a repro save.
Yes in 0.13.5 the Test spell in the save can only be absorbed 10 MP however in the newest build you can absorb the whole 35 MP.
SAVE2.zip
(119.18 KiB) Downloaded 56 times

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Interkarma
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Joined: Sun Mar 22, 2015 1:51 am

Re: Exploit: spell absorption increase your magicka when AoE yourself

Post by Interkarma »

Thank you. :) Will take a look at what's happening when I can.

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Interkarma
Posts: 7236
Joined: Sun Mar 22, 2015 1:51 am

Re: Exploit: spell absorption increase your magicka when AoE yourself

Post by Interkarma »

Thanks again. I found my error in conditional and have fixed this now so my earlier change works as intended.

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