"The main motif was an ogre, and each one was designed by following the keyword which we had for each of them. We think that you can see their characteristic just by looking at them." - Concept of the Deadly Six.
"Wisps all have 3 legs, but if you look closely, each has different shape in legs too." - Concept of the Wisp.
"An early development idea which the gears are rotating in different direction. Looks painful if you get sandwiched." - Concept of Windy Hill Zone 1.
"The concept was totally new, so we couldn’t decide the direction of the design. It was tough as we had to re-make this first stages over and over." - Concept of Windy Hill Zone 1.
"The inner cylinder was very confusing when designing as what it was ceiling would be a ground in next second." - Concept of Windy Hill Zone 2 (Nintendo 3DS)/Zone 3 (Wii U).
"When you hear desert, you will imagine pyramid and oasis. It’s a stereotype, but we felt it was very understandable." - Concept of Desert Ruins Zone 1.
"We were requested a simple design, but that makes it hard to create a sense of scale, and made Sonic look small. Taking balance to achieve this was very difficult." - Concept of Desert Ruins features.
"When you play the game, you actually can’t see the side part of this stage, but the design is based on a hornet’s nest." - Concept of Desert Ruins Zone 2 (Wii U).
"When you design a tropical stage, you really want to take an holiday and go there. I felt this way especially when I was making this stage." - Concept of Tropical Coast Zone 1.
"You are not copying the real world, so we sometimes get lost what kind of design is the best." - Concept of wall patterns in Tropical Coast.
"It looks flat in this art, but it is actually on a huge sphere, so it was very difficult to design." - Concept of Tropical Coast Zone 1.
"Very early image of the Casino stage. There are too many blue color and may be hard to find Sonic." - Concept of Frozen Factory Zone 3.
"There are various types of plants and trees, we re-designed many times and it was very tough to make it look “Jungle”." - Concept of Silent Forest Zone 1.
"It may be hard to recognize, but we thought it’s funny if water was coming out from the eyes and nose of Moai in the background, so we did that." - Concept of Silent Forest Zone 3.
"Did Eggman run out of budget in the final stage? You can see many patches and looks very easy to tear down this place." - Concept of Lava Mountain.
"We wanted to make it look like an army, so we were thinking to make an another color version for the leader. But unfortunately, we didn’t have chance to use the leader type." - Concept of the Anton.
"This is one of the few enemies which are an original design for Lost World. The motif is ant-lion." - Concept of the Antlion.
"When we design this Buzz Bomber, we decided the concept of the eyes of all enemies for this title. So we tried various type of eyes on this enemy." - Concept of the Buzz Bomber.
"Instead of adding details, we wanted make it simple but huge, and wanted to make the players feel the largeness with this gap when we design this." - Concept of giant Caterkiller.
"It was the very first enemy we designed in this title, so we had many various idea to this enemy. We wanted to make the design simple so the entire silhouette will fit in single sphere." - Concept of Moto Bug.