Stat Items

[Coy]

Items that you need to wear to gain a numeric bonus to a stat modifier, such as a Headbands of Intellect, it goes without saying you gain the direct bonuses of the stat increase.

But what happens when the stat affected changes key things to a character?

For example, for a human 3rd level wizard with intelligence of 18, he gains 6x(2+1+4) skill points.

He then buys a headband of intellect +2.

The real questions are:

Will he retroactivly gain skill points of 6x(2+1+5)?

If so, how do you adress the complications of taking it off (such as losing allocated skill points, changing DC's of spells in effect, loss/gain of extra spell slots?)

[Geiger Counter]

I forget where it says this but no, temporary bonuses do not increase skillpoints.

[Mongoose87]

Temporary bonuses to intelligence do not increase skill points. Permanent bonuses to intelligence do not retroactively increase skill points.

[paddyfool]

Changes to Int (+ve or -ve) do not alter skill points already assigned, since those skills have already been learned/not learned when you were more or less smart. This can get a little fiddly when building a character at higher levels if they have permanent boosts to their skill points, especially if these are not directly level-dependent (e.g. Tomes).

Changes to Con, however, do alter its effect on your total HP across all levels.

[herbe]

And what about wish-granted inherited Intelligence? Is it add more skill point for previous skill points or only to future?

[danzibr]

Temporary bonuses to intelligence do not increase skill points. Permanent bonuses to intelligence do not retroactively increase skill points.

This is exactly right. So for wish, if your modifier goes up then you get more skill points for future levels, not past levels. It's not like con in that sense.