Thongor and the Dragon City — Lin Carter

Xothun had ruled in Omm for a thousand years -- master of strange powers, yet slave to his craving for human blood. The lost city lived only to serve -- and feed -- Xothun.... Then came the barbarian adventurer, Thongor of Valkarth, with a city to free, a princess to rescue, glory to win -- and his mightly sword to pit against Xothun's wizardry!

This is the second in the adventures of Thongor, greatest warrior of the forgotten continent of Lemuria!