"You cannot breed or buy Kairos, you have to summon him! First you have to buy the Perch of Kairos (750,000 coins). Then you need to gather three artifacts: the Chronolith, the Time Claw and the Statue of Kairos. The artifacts are built by collecting 21 time fragments. They can be won on the Dragon Races or bought for 2,700 gems total."
To breed a Gold Dragon, it has been established that the elements metal and fire must be present. This means many combinations are possible. The Gold Dragon can be bred at either the Breeding Cave/Epic Breeding Island.
It goes on to say that the breeding time is 48 hours, or 38 hours and 24 minutes in an upgraded Breeding Cave/Island.
You must, however, be at least Level 17 before you are able to breed the Gold dragon.
Note: Level 17 is your required level, not the required level of your dragons.
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Dragonvale Kairos Dragon
"You cannot breed or buy Kairos, you have to summon him! First you have to buy the Perch of Kairos (750,000 coins). Then you need to gather three artifacts: the Chronolith, the Time Claw and the Statue of Kairos. The artifacts are built by collecting 21 time fragments. They can be won on the Dragon Races or bought for 2,700 gems total."