Can I move all monsters and then attack with them, eks to get the most out of swarm ability.

I believe the rules state that once you "activate a monster" you must finish its turn completely before activating the next monster. Same goes for the players.

Aye to the above!

However, what you can do, is to charge a few beastmen or the like in first... then get bonus to the swarm for them...

I thougt sow ass well,

edderkoppen said:

If you charge a few beastmen first, there won't be anything left to swarm!

Although not as effective, you can begin your swarm attack with the first monster with the swarm ability. You wont get the bonus but the next one you attack with will, and the next one you come in with the bonus will be bigger yet. I have used an ambush strategy with swarming monsters with much success...