The player research page for 925 is awesome:

https://gswiki.play.net/Research:Enchant_(925)_Formula
However it did not contain any information about exactly how much ensorcell tier increases the difficulty of an enchant Searching the forums also didn't turn up anything aside from the anecdotal. So I decided to use the neat encumberance/coin method at the bottom of the page to begin answering this question. Here's what I did:

**1. **Bought two vultite short swords from the Landing. These are 4x, nothing else on them.

**2. **Browbeat a young sorc into applying a T1 to one of the swords.

**3. **Took my wizard to the FWI bank.

**4. **Withdrew/deposited coin in a loop and 925'd the non-T1 sword each time to check difficulty. Used binary search to determine exactly how many coins put me at the 97% chance breakpoint ("horribly unlucky"). This turned out to be 28855 coins (+/- 5 coin error factor).

**5. **Then binary-searched the 90% chance breakpoint ("barring bad luck"). That turned how to be 30870 coins. That's a different of 2015 coins for 7 points of difficulty, or 288 coins per point.

**6. **Now I swapped in the T1 sword and redid step 4 to determine the 97% breakpoint again. Result was now 26835 coins.

So the difference between the 97% breakpoint of the T0 and T1 swords was 2020 coins. That is, the T1 sword is 2020 coins more difficult. Using the math from step 5, this means it is about

**7 points more difficult**. In the context of all the pluses and minuses to enchant, a mere 7 points isn't all that much. Therefore I strongly doubt that that this same number can be extrapolated to higher tiers. That is, I suspect a T2 would be more than 7 points harder than a T1, and so on. I plan on continuing this research as I get the sword ensorcelled upwards, redoing all the above steps for each tier. (If any sorcs want to donate necro to the cause...)

It would also be neat if a sorcerer could research the opposite question using a similar method -- that is, exactly how much harder does enchant value make ensorcell? However, I'm not sure encumbrance works the same way for ensorcell; the coin trick is certainly the easiest way to fine-tune enchant difficulty for a wizard.

(If I fucked up spectacularly somehow in the above steps, I'm sure you will let me know.)