All four flowers, or all four seasons.
You hold all four flowers or all four seasons. It is two faan.
Bonus tiles are drawn and set aside automatically with a replacement tile, so this accumulates without any decision from you. Holding all eight is both sets, and scores accordingly.
Nothing to build. What is worth knowing is that each bonus tile draws a replacement, so a run of flowers gives you extra looks at the wall. That is a real if invisible advantage in a close hand.
Expecting it often. Four specific tiles out of 144 landing in one hand is rare, and it cannot be pursued. Treat it as a windfall rather than as part of a plan.
It adds two faan to whatever the hand scored, and it includes your own seat flower, so Matching Flower scores alongside it. It can never appear with No Flowers, which requires holding none.
Do I need all four flowers, or four bonus tiles of any kind?
All four of one kind. Two flowers and two seasons is not a complete set.
Does holding all eight score twice?
Yes. All four flowers and all four seasons are two separate complete sets.
Do bonus tiles cost me a turn?
No. Each is replaced immediately from the back of the wall.
Play Mahjong Winds
Every win shows its faan line by line, using the table on this page.