Warhammer

Warhammer is an item which has a chance to drop after successfully defending an Item Island.

The Ring of Command of offensive items. The Warhammer gives one of your commanders the ability to throw themselves at the enemy to deal damage and knock them back (Useful to drown enemy units.)

Warhammer can be upgraded to level 2 for 8 coins and level 3 for 14 coins, each increases its power even more.

Once used in battle, the ability will have to recharge for 40 seconds to be used again. A small icon of the skill will appear over the commanders unit for a short amount of time, when the ability has been recharged.

Be careful when using it, the attack can harm your other squads but does not harm the squad that used it

As with most items in the game, once it is assigned to a commander, it cannot be removed. You can choose Warhammer as a starting item once you have unlocked it.

Recommended

 * Suitable for all three unit classes.
 * Best used with Infantry so they can fairly easily handle Brutes, the most difficult unit for them to handle.
 * If you have poor pike placement, you can warhammer the attackers so your pikes will have time to recuperate.

Con of Warhammer to Bomb

 * While on a cooldown, if bomb is upgraded to level two a second bomb can be thrown shortly after the first when needed which may be necessary at times, whereas warhammer you must always wait for the cooldown to finish before using it again.

Link
*Source: http://badnorth.wikidot.com/warhammer