Crushing Wave

Crushing Wave
This weapon stores the unstoppable force of the oceans fury deep within. When this weapon is used this power occasionally comes to the surface, crushing enemies beneath a torrent of frigid water.
 * 5% Chance of 3 ticks of 30-40 Cold and 30-40 Bludgeon Damage over 6 seconds (180-240 damage, 210 average)
 * Average of 10.5 damage per attack.

Crushing Wave Guard
This item stores the unstoppable force of the ocean's fury deep within. When the wearer of this item is successfully attacked in melee, this power occasionally comes to the surface, crushing enemies beneath a torrent of frigid water.

Damage is approximately 25 to 36 points of cold damage and 31 to 37 points of bludgeoning damage.

(Combat): Jungle Troglodyte hit you for a total of 3 points of bludgeon damage after 5 were blocked by damage reduction. (Combat): You hit Jungle Troglodyte for 31 points of cold damage. (Combat): You hit Jungle Troglodyte for 30 points of bludgeon damage.

(Combat): Jungle Troglodyte hit you for a total of 5 points of bludgeon damage after 5 were blocked by damage reduction. (Combat): You hit Jungle Troglodyte for 25 points of cold damage. (Combat): You hit Jungle Troglodyte for 36 points of bludgeon damage.

Proc rate appears to be low (estimate 5%) although I did experience a run of 3 consecutive procs.