That's how I'd expect it to work...

You need friendly unit next to the charging unit to get the bonus when the unit lands it's attack.
But I'm not sure, how this works:
1. Move unit 1 to position near enemy, without attack yet
2. Move unit 2 to position near unit 1, getting overhelm bonus.
3. Use attack on unit 1. Does it count as charge with bonus DMG or does it not cause movement and attack are separate actions in this case?

charge mechanics are a separate question....

Unit A runs to the target. Doesn't attack.
Unit B runs to unit A.
Unit A gets the buff (B also).
Unit A attacks.

Charge is based on your starting position, not when you click attack.

Originally posted by Astronimo:

Unit A runs to the target. Doesn't attack.
Unit B runs to unit A.
Unit A gets the buff (B also).
Unit A attacks.

Charge is based on your starting position, not when you click attack.

Oh, that explains charge of phasing creatures as well. Thanks

So this means you waste a bonus if you charge an enemy, even if there is a friendly unit next to the enemy!

Originally posted by Darkreaver1980:

So this means you waste a bonus if you charge an enemy, even if there is a friendly unit next to the enemy!

i'm not sure where you're seeing that

IIRC - you originally couldn't use the overwhelm bonus among two charging units, because you had to do the 3-hex travel in one go.

But this was changed so you can move anywhere by any means (incl teleport) and it's going to count the total distance from your starting point.

So now you can charge two units into a position adjacent to the target and to each other, then attack with both boni.

Originally posted by Darkreaver1980:

So this means you waste a bonus if you charge an enemy, even if there is a friendly unit next to the enemy!

No, if you end your movement near a friendly unit with said perk.