That's an 800 point unit. It should be tough.
If you're going to meet them in combat, there are some good hexes that would help. Curse of the midnight winds forces re-rolling 6s. That's excellent against a unit with killing blow. Anything that reduces their ability to hit (so, Light of Battle on your unit, Iceshard Blizzard, Miasma, on them) should help.
I think it all depends on the make up of your army. Some will have enough redirecting units to keep the TG out of major combat for the whole game. Others will be able to buff/debuff enough to take the unit on. Still others will have enough ranged to cripple the unit, even with the banner and raises.
A Steam Tank in the front would only be in base with four models, so 12 could attack in horde. Even with Killing Blow, it could hold that unit up for quite some time.
Lots of options, I think.