火焰、大地、空气、流水、寒冰，都不能阻挡钢铁与魔法。

Objectives

消灭个元素。

Tiers

1. 1 : 10 objectives completed
2. 5 : 100 objectives completed
3. 5 : 500 objectives completed
4. 5 : 1 000 objectives completed