I love this game ! ice Cap be REALLY cool , along with Twinkle Park . when you enter Twinkle Park , you have to get in a bumper car and drive down a long but fun road . it have ton of loop and hairpin curve ... drool . and the ending of Ice Cap be cool , where you have to snowboard down the mountain to avoid a avalanche and then skid down and grab the Emerald on you way . the Storyline : Sonic be return to Station Square after a long journey and run across a liquid monster name Chaos . you have to fight he , and he turn into a puddle and slip down the sewer . then he be at the beach and see tail in he new plane , out of control . you have to get through Emerald Coast to save he . tail show Sonic a Purple Chaos Emerald -lrb- if they be emerald , why be just the Ice Cap one green ? O. o -rrb- and tell he it be the power source of he new plane . then he tell Sonic to meet he at he shop in the Mystic ruin . sonic arrive , but he be stop by Robotnik and have to fight he . I forget the rest , but at one point you have to fight Knuckles . when you be Amy , the end be pretty sad : e-102 die and the bird 's family fly away with the bird .  Chao : the Chao , also know as a-life , be little blue and green coo thing that remind many sonic fan of Tamagotchi . you have to feed they and let they sleep . you 'll notice that when you attack a enemy in a Action Stage , a animal inside a green bubble float out . grab the animal , and when you go to the Chao Garden the animal you collect will fly out . hold one up to a Chao and after glowing green , it 'll get a characteristic of the animal . only animal that have spark fly from they do this , though . if you give you Chao enough animal , -lrb- 20 once , 50 the second time . -rrb- it 'll sit down and form a white cocoon around it . the cocoon will fade and the Chao will look different and be a different color . if you Chao be limp or if you hurt it a lot , it will make a cocoon and die .  so , all in all , this game rule !