Dervishes do not charge like normal units. Instead, declare the unit you wish to charge, resolve charge reactions and roll the charge distance as normal. Turn the Dervishes so they are facing the centre of the enemy unit, and then move the unit forward. If the charge is successful, the Dervishes do not stop once they reach the target but always move their full charge move (through the target unit), emerging on the other side and moving through multiple enemy units if they have enough Movement to do so (stopping within 1" of any friendly units). If they ever end their movement within an enemy unit, place the Dervishes 1" behind the enemy unit.
If they cannot be placed behind the enemy unit due to there not being enough space, they are removed as casualties after resolving their attacks. Any unit passed through in this manner takes D3 Strength 3 hits with the Poisoned Attacks special rule for every Dervish in the unit.
An enemy unit that charges a unit of Dervishes suffers D3 Strength 3 hits with the Poisoned Attacks special rule for each Dervish in base contact, resolved like Impact Hits. Combat is then resolved as normal.