Ravens

[Ruvanal]

The mlvl of the ravens for figuring the to-hit chances is
mlvl=caster level -2 +skill level
Their AR should be if I am reading it right 100+(slvl-1)*15.

Most of their chance to hit will end up coming from their mlvl, so if it is less than the monsters they are attacking do not expect many hits.

They use the same modifier for blinding targets as is used on items. The base setting for this is -1 though.

From AS:

Hit Blinds Target
Decreases radius of awareness similar to the Necromancer Curse: Dim Vision.
The formula is as follows:

Chance = 50 + (Attacker Level + (Bonus * 4) - Defender Level) * 5
Where the bonus is how many items of hit blinds target the character has -1. Some items have something like hit blinds target +2, which means they count as 2 items for the bonus calculation. Missile Attacks are at 1/3 this chance.

The level of Dim Vision that's cast on the target is equal to (Chance - Roll)/5+1, max of 20.

So if you do not get their level up some, they will have problems contending with the bonus=-1 and monsters that have levels greater then theirs. The duration of the Dim Vision will depend on the level of effect tha tactually ends up being used.