I think you mean Mind/Cold. I don't have a Mind/Cold, but I have some decent experience with Mind Control. Mind Control is very powerful, especially in low levels. The attack chain of Dominate-Mezmerize-Levitate can carry you a long way. You can take out single targets easily, or spread those powers around to protect yourself. Add in Confuse and Mass Hypnosis, and it is very safe. The lower level Cold powers won't help you much solo, as the ally only shields will be worthless.
In upper levels, you will be lacking much AoE damage, and you won't get the damage boost that other controllers get from a pet. Your only AoE damage comes from Terrify. You'll get a little help from Confuse powers, but your damage slows down in upper levels. On the other hand, you will get some great AoE control and some powerful debuffs. In upper levels, you'll probably want to team more than solo.
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My favorite character is a Mind/Cold. In part that's because I simply like the concept, but the sets do compliment each other nicely.
The first main advantage is the Stealth from Arctic Fog. You can use it to stack with Super Speed or a Stealth IO to go invisible to most enemies. An invisibile Mind Controller is at a huge advantage, due to having three aggro-less mezzes that let you set up the battle field in near total safety prior to launching the fight. Unlike many other sources of Stealth, Arctic Fog also never suppresses, so you will permanently have a 35ft stealth radius to help keep you out of trouble.
Second, both Mind and Cold benefit tremendously from Recharge IOs. And it just so happens Cold Dom offers three powers you can slot Luck of the Gambler +7.5% global recharge in.
Now, for the headaches (kind of). Firstly, one of Cold's main strengths is elite boss and AV fighting. Mind Control, however, sucks at dealing with AVs worse than almost any other set due to lack of Containment and no pet to hide behind. For dealing with AVs you pretty much have to team. Not that this is so bad, because once the team gets in front of you, you end up being a huge asset. And since AV fighting makes up a much smaller portion of the game than fighting huge spawns it evens out rather nicely.
The second frustration comes from lack of AoE Containment for dealing damage solo. You can put enemies to sleep with Mass Hypnosis, but Sleet (your best debuff) will wake them up. This prevented me from soloing much with my Mind/Cold up until he was pretty well IO'ed...
...but then I finally got there, and OMG am I glad I did. While certainly not a farmer, the can of butt whipping Mind Control can unleash is pretty amazing when you consider how much sheer control it offers on a team. My "secret" (not really) is to go with the Primal APP Pool and take Power Boost. I run 0x8 missions (of nearly any enemy type) and approach it like this:
[before the enemies are aware]
- If there are straggler enemies, confuse them first, they will probably run toward the larger group. Same applies to any enemy simply too dangerous to risk breaking out of mezzes, like Sappers or Master Illusionists
- Power Boost
- Mass Confusion
- Total Domination (AoE hold which when PBed will last 48 seconds... do you see where I'm headed here?)
[the enemies become aware of you after TD; although one alternative is to cast Mass Hypnosis first so anything missed is still sleeping and anything hit is held, at least until Sleet likely wakes them up]
- Sleet, which is slotted with 4 damage procs and a -resist proc
- Terrify, which is slotted with 1 damage proc and a knockdown proc in case some enemy got missed by both MC and TD
- Energy Torrent, which has a 60% chance for knockdown on the offchance some enemy is STILL active. This is also slotted with a damage proc and the +recharge proc
- Mass Hypnosis toward the back of the crowd, just because. And I plan to reslot this soon with a chance to heal proc
Now as you can imagine this isn't the fastest process ever because the recharge on TD and MC is about 60 seconds. But for a build that supposedly has low damage it definitely puts out a lot more destruction than a lot of people give credit for, IMO. Just as long as there are no Avs or elite bosses, for which I am happy to bring some friends. 
What are people's thoughts on this combo? How would this fare solo?
Just rolled one last night and it seems pretty good, but at low level, it's hard to tell. Anyone out there have a high lvl mind/ice running around or in stock?
Thanks for any thoughts on this.
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