I got lucky on a roll and won the normal thunderforged version of Horridon's Last Gasp.
What i found with this trinket was that it can stacked on top of each other. I had it during trash at least stack up to 3 and while doing so it would reset the buff timer.
Here is our 9:25 fight against council.....http://www.worldoflogs.com/reports/r...?s=4265&e=4831
If that log is made private try http://www.worldoflogs.com/guilds/229328/ later she might upload them after raid. Worst case i can go do an lfr boss and show those logs.
Anyways it is under the name Cloudburst on buffs gave me 124392 mana in a 9:25 fight. Ticked 54 times procced 11 times Average mana gain of 2303.6 per tick.