Sonic Adventure 2

This is a very simple achievement. All you need to do is have two Chao reach maturity having been raised by a Hero and Dark character respectively. Raise one with Sonic, Tails and/or Knuckles, and the other with Shadow, Rouge and/or Dr Eggman. Raising consists of petting, feeding and bringing them Drives and animals from the stages.

After a certain amount of time spent in the garden with the Chao in question, they will mature, attribute levels etc have no bearing on this, it's purely based on time spent in the garden with the Chao in question. You will know your Chao is maturing when they go into a cocoon shaped like a Chao head. When they emerge they will be an adult and will be either Hero, Neutral or Dark.

Hero = Halo above the head.
Neutral = Sphere above the head.
Dark = Spikey sphere above the head.

As long as you raise one adult Hero and one adult Dark Chao, you will unlock both the Hero and Dark gardens (accessed from the lobby, up and downstairs respectively) and you have your achievement.

AceCard's solution basically summed everything up, I just want to mention a couple of things. What i did was as sonic (when you have two unhatched eggs) throw one at the wall to make it hatch (this will be the good one) then let the other hatch naturally (bad one) you also want to jump on the bad one a couple of times to change it's alignment. as sonic raise the good ones stamina up to about level 9-10 by feeding it fruits, this will cut down the time you need to wait for it to evolve from about 3 hours to about 1.5-2 hours. Now wait for the good one to evolve and after the good one has evolved leave the chao garden and come back as shadow. Now as Shadow raise the bad chaos stamina to about level 9 and wait for it to evolve (shouldn't take terribly long) and the Heaven or Hell achievement will pop up, also raising the stamina will help towards the Chao Raiser achievement if you don't already have it

I Hate this whole Chao system, so Ill tell you exactly what I did to be done with this in 2 and a half hours approximately.

Hero Chao:
Hatch an egg using any of the hero characters and as soon as he is out of the egg start petting him with B untill the ball above his head becomes very blue and it develops angel wings, this means that he is going to become a hero chao when he evolves.

Dark Chao:
Same as the hero chao, pet him untill the ball above his head becomes Pink, a dark pink, and he develops devil wings, this means that he will become a Dark Chao when he evolves.

So, with that said, after you "oriented" your chao either way, if you are doing exactly what I did, you have to feed him coconuts from the trees until his stamina gets to level 10, you may have to wait for three "harvests" of coconuts to get him there, now you just wait untill it evolves. Doing this, it took me around an hour and fifteen minutes for each of them, from the time they hatched to the time they evolved.

Also, I Dont know if this matters but I used eggs from the blackmarket, and gave a dark fruit for my dark chao and a hero fruit for my hero chao.

I have not replicated this, so if you are doing as I did please post your findings as to the time it took for you chao to evolve, or any improvements you find to that strategy.

I thought it’d make this guide just to shine light on some mechanics people may not know about. You technically only need one character to get both the dark and hero Chao. The way to do it, extreme Chao abuse. If you play as a HERO character all you have to do is throw the Chao against the wall, bounce on him, etc until his orb above his head becomes red. If you want a good Chao as a HERO then just pet your Chao until the orb above he s head becomes blue. Then the opposite if you play as DARK character. Also it doesn’t matter how you hatch the eggs for I threw all mine at the wall and was still able to make both chaos.

Also the most helpful mechanic I found was how evolution is affected by food. Turns out if you feed your Chao 50 fruit, your Chao will automatically start to evolve to its respective side. You can use any combination of fruits. I personally used Chao fruits just so I could get my chaos ready for the racing and karate events.

I’d say with the right luck from the black market or if you have plenty of trees in your garden, you could easily get both these guys evolved in 2
hours or less.

One last thing. If you need rings, here’s a video on how to get infinite: Still works 2023