Time travel in Sonic 2

We interrupt our regularly scheduled analysis of Sonic 3's interactions with the VDP for some very exciting news.

Earlier today, Hirokazu Yasuhara, lead game designer for Sonic 1, 2 and 3, was present at the video game developer conference Digital Dragons, where he held a presentation on how to make games "fun". Who in their right mind would have expected that after 25 years, all the way from Krakow, Poland, he would share with us these amazing production sketches for Sonic 2?

Here's a brief recap, adapted from articles on the Sonic Retro wiki. Back in 2005, vested Sonic researcher ICEknight managed to secure some enemy sketches from the Sonic 2 production staff. Between the six images, though, what got everybody's attention were the comments next to the sketch for the "Bumper" enemy:

SONIC 2 ENEMY PICTURES BUMPER Location of appearance: Desert Zone (present) Step on it and it sends [Sonic] flying far away OLD BUMPER Location of appearance: Rock Zone (past) Property: Same as above (color change)

For the past twelve years, that little blurb was all the information we had on Sonic 2's early time travel elements. The sketches revealed today not only give us rough names for all the Zones that were planned, but also shed new light on a minor mystery with the final game.

Internally, Sonic 2's levels are stored in a seemingly nonsensical order, with several empty slots scattered about, not unlike monster species in the first generation of Pokémon games. Turns out, they line up more or less perfectly with the prototype order seen in the sketches, and the above timeline shown by Yasuhara during his presentation:

Internal order 00 - Emerald Hill Zone 01 - (unknown) 02 - (Wood Zone) 03 - (unknown) 04 - Metropolis Zone 05 - Metropolis Zone 3 06 - Wing Fortress Zone 07 - Hill Top Zone 08 - (Hidden Palace Zone) 09 - (unknown) 0A - Oil Ocean Zone 0B - Mystic Cave Zone 0C - Casino Night Zone 0D - Chemical Plant Zone 0E - Death Egg Zone 0F - Aquatic Ruin Zone 10 - Sky Chase Zone

Timeline グリーン (Green) オーシャン (Ocean) ウッド (Wood) サンド (Sand) メトロポリス (Metropolis) トロピカルサン (Tropical Sun) ブルーオーシャン (Blue Ocean) ヒルトップ (Hill Top) ロック (Rock) オイル (Oil) ダスト (Dust) デスエッグ (Death Egg) ヒルトップ (Hill Top) ブルー (Blue) カジノ (Casino) ケミカル (Chemical) ジェノサイド (Genocide) ネオデスエッグ (Neo Death Egg)

Sketches Green Hill Zone Ocean Wind Zone Woods Zone Sand Shower Zone Metropolis Zone Tropical Plant Zone Blue Lake Zone Hill Top Zone Rock World Zone Olympus Rock World Zone Oil Ocean Zone Dust Hill Zone Casino Night Zone Chemical Plant Zone Genocide City 1 Zone Genocide City 2 Zone

In the next few articles, we'll look at Sonic 3's own internal level order and the stories it tells us.