The Iridescent Garden is a special building released as a reward for participating in the top two leagues of Guild Battlegrounds. It is classed as a decoration and provides happiness and can be polished. Fragments of the Iridescent Garden may also be won from the Guild Battleground Rewards. It takes 100 fragments to make a full Iridescent Garden.
The building comes in three variants but they only have visual differences though.
If the Iridescent Garden is properly chained to the left of a Great Elephant a 5% defense boost for the attacking army, 1 Forge Point and 3 Goods is added to the Elephant. The number of Iridescent Gardens that can be chained to a single Great Elephant is only limited by city space and availability of the Iridescent Gardens.