Play Slot Machine for Extra Coins and Diamonds
1) Set up your defenses around the slot machine. Try for one row of wallnuts on the right side, one or two rows of sunflowers on the left, and fill the rest with pea and snow pea shooters.
2) Protect the lawn mowers as each are worth a Gold Coin at the end of the game, so don't let them mow the zombies.
3) Stop gathering sun around 1900 sun points. At this point, the garden should be full, so getting the extra 100 points to win should be easy. Just collect enough sun to offset the slot machine.
4) Keep the slot machine spinning! It will randomly drop one or three gems as long the patience lasts.
5) If the Zombies get close to the mowers, end the game. Simply collect the sun lying on the field to end the game.