I think the biggest mistake people who use the steam tank make is that they use it unsupported. Empire as a whole must make use of each other in order to remain effective, and the stank is no exception
A combined charge from some knights or a block with the stank and you will break nearly any orc unit
Dont forget that it has 10 wounds and a 1+ armor save and Toughness 6. Thats enough to keep it alive once it starts hurting
I think the key is to put it near the center, and move forward. There are two things that can happen by doing this. Its unlikely that the enemy will KILL it, but wounding it is a possibility. Therefore, its either going to steamroll the enemy and really kick ass, or its going to take some wounds and you can park it in the center and cause terror checks and hold ground (well)
Good luck, and sorry the stank hasn't faired well for you (maybe try taking two....
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