/** Iron Era */
BED_DEFENSE_I = "bed_defense_i",
DESTRUCTION_I = "destruction_i",
ALTAR_I = "altar_i",
/** Diamond Era */
DESTRUCTION_II = "destruction_ii",
MAGIC_I = "magic_i",
ALTAR_II = "altar_ii",
/** Emerald Era */
MAGIC_II = "magic_ii",
ALTAR_III = "altar_iii",
