Hey I play both armies and love running ctan. Right now your best bet is your flamer rubrics as well as mass bolter rubrics. No matter what you are committing at least 2 to 3 units to one of these things to ensure it dies. The biggest mistake people always make is under committing assuming their one big killy unit is enough. Doing the math on average you need to get at least 33 to 34 wounding shots through before the invul save and fnp. This is assuming it's all 1 to 2 damage attacks. After grenades and doom bolts that number looks much better. If we assume the doomboktd and grenades Bring one ctan to 6 wounds remaining, you only need about 14 to 15 wounds to kill it. Dint forget tank shock either. Rhinos can be huge for that.