Another new 8th level spell, Enhancing the Divination school Options

[Sikret]

Here is an idea for a new 8th level spell of divination school. Comments are most appreciated.

Note that if we decide to implement the other new divination spell, Premonition (either as a replacement for Mislead or not), these two spells need to be rebalanced together (and should not cumulatively work with each other).

Foreknowledge (Divination)
Level: 8
Range: 0
Duration: 1 turn
Casting Time: 8
Are of Effect: Self
Saving Thorw: None

By means of this powerful spell, the mage can foresee the events of the immediate future to some considerable extent and can prepare himself (both mentally and physically) for the events which are going to happen. The mage gains +4 bonus to Armor Class, +1 bonus to THAC0 and saving throws and +1 bonus to casting speed for the next 10 rounds. These effects will remain for the spell's duration and won't be dispellable.