If the Hormone value of a MetaElf falls below sixty (60), there will be a higher chance of breeding failure. The chance increases as a MetaElf’s hormone decreases. Once it reaches zero (0), a MetaElf will not be able to breed. Each time of breeding consumes 20 points of Hormone value. If players see crossed swords instead of a heart, it indicates that the MetaElves are in combat formation and cannot be used for breeding.