I sing the praises of Earth Mastery

[Heraclea]

Really, this is a neglected gem.  Usually I end up taking Energy Mastery on a tanker.  It does one thing well: it gives you a place to slot one or two more Performance Shifter procs. 

 

Earth Mastery, though, helps you in even more ways.  I have two of the powers on my newest tanker (Willpower/Mace).  Being Willpower, she doesn't need Perf. Shifter mules.  I took two powers from the set: Salt Crystals and Quick Sand (sic). 

 

Salt Crystals was and is a huge AoE; sixteen feet IIRC.  It takes accuracy enhancements, which means that it taunts every mob it hits.  The fact that it 'sleeps' mobs is your least concern.  It takes sleep sets, which enable some interesting procs inc. a chance for self heal.  And it does not require many slots to be effective.  It debuffs defense of everything it affects. A worthwhile first tier power.

 

Quick Sand is annoyingly a ground-circle targeted power out of the box.  You're gonna want a macro.  It takes Slow sets, which means it can use the Trap of the Hunter proc.  It needs no accuracy, which means that it is effective with only the default slot.  It also slows mobs it effects, keeping them close.  It also debuffs defense,  A worthwhile second tier power.

 

I have not taken any of the other powers from the pool, which do holds and damage.  For a melee controller tank build, these two have a lot of potential and seem quite worthwhile.  No that in addition to Willpower we have Bio, Radiation, and other armors that do not need endurance relief, I think this pool is worth a closer look.

[Scranker]

I had a Dark Armor/Stone Melee/Earth Mastery Tanktroller (perma stunned everything--Oppressive Goom + spamming Fault) back on Live that I used specifically for running PuGs. Since I was usually set at +3x8 or +4x8, Quicksand (in particular), Salt Crystals, and Stalagmites were great for the -def so that the lower level folks on the team could reliably hit stuff. (And yeah, Salt Crystals' huge radius of 30' was also awesome for grabbing aggro.)

[ninja surprise]

I bind lshift+lmouse to Quicksand so it's easy to put down, but a target-macro would work well too.

Love those two powers. Even though Salt Crystals is a sleep, it's fun to pop it on a spawn then go punch another spawn, and the Salty mobs will be taunted when they wake.  Great way to keep targets trickling in to be defeated.