Garden Controls
You control the garden by manipulating a hand-shaped cursor. Use the d-pad on your Game Boy Advance to move the cursor around the garden. Move the cursor over a chao and press the "A" button to pat your chao. Pick up items like toys or fruit scattered around the garden by hovering over them and pressing "A." The "L" shoulder button opens up the store, and the "Start" button pauses the game. These simple controls are all you need to manipulate everything in the garden.
Obtaining Chao
You can purchase chao from the shop in the garden by spending rings obtained in the main Sonic Advance 2 adventure. You can also get chao by transferring them from Sonic Adventure 2: Battle on the GameCube via the Game Boy Advance transfer cable. The egg colors in ascending order of rarity are normal, silver, gold, ruby, sapphire, amethyst, emerald, garnet, aquamarine, peridot, topaz, onyx, purple-gray and glowing yellow. The rarer ones can be purchased in the shop after meeting certain requirements. The purple-gray chao can be obtained only after you have purchased every other type of egg that comes before it. A moon chao will hatch out of this egg. After buying the moon chao egg, you will be able to purchase the glowing-yellow egg which hatches into a sun chao. Each of these super-rare eggs costs 20,000 rings.
Store Items
Besides eggs, toys and fruit can be purchased from the store. Toys are placed near your chao for their enjoyment while fruit is consumed by your chao, giving it various statistical boosts. The toys available for purchase are trumpets, rubber ducks and televisions. The television appears in the store three in-game hours after you purchase the duck. It costs 8,000 rings. The fruit available include oranges, squash, strawberries, apples, grapes and mangos. The most expensive fruit, the square apple, boosts your chao's "Swim" stat by three, its "Fly" by one, its "Run" by two and its "Power" by two. It also lowers its stamina by five.
Mini-games
The two mini-games available in the garden are Chesse Bounce and "Matching." Chesse Bounce tasks you with controlling a trampoline-holding character trying to bounce another character into floating rings. Use the d-pad to move back and forth. Hold "B" to speed up. Pressing "A" right when the character Chesse lands on your trampoline will make him bounce higher. In "Matching," you must turn over cards to match pairs. The cards are arranged by your chao. As your chao is moving the cards, you can press the "A" button to cause it to trip and reveal the card's face without penalty.