Turn 51
Devasura easily took T'ien Ch'i's province. T'ien Ch'i made a half-hearted attempt at attacking my southern border, but it was a weak attack. He also tried once more to dislodge Vanheim from his capital, without any more success than the last time.
Here's a shot of my armies attacking T'ien Ch'i in swampland, which gives units without swamp survival penalties in attack and defence.