Oskar van Deventer (born 1965) is a Dutch puzzle maker.^[1] He prototypes puzzles using 3D printing. His work combines mathematics, physics, and design, and he collaborates at academic institutions.^[2][3][4] Many of his combination puzzles are in mass production by Uwe Mèffert and WitEden. Oskar van Deventer has also designed puzzles for Hanayama.

He was a Guinness World Record holder for his 17×17×17 "Over the Top Cube" Rubik's cube-style puzzle from 2012 to 2016,^[5][6] when it was beaten by a 22×22×22 cube.^[7]

In addition to being a puzzle maker, Oskar is a research scientist in the area of media networking and holds a Ph.D. in optics. He has over 100 publications, over 80 patents applications, and hundreds of standardization contributions.^[8]

Mass-produced puzzles

• Gear cube: Previously named "Caution Cube" because there was a big chance to pinch your fingers with the gears.^[9] It was mass-produced by Mèffert's in 2010,^[10] but over time it appeared as several copies and shape mods of the same design.
• Gear Cube Extreme: A bandaged version of the Gear cube, where 4 gears are replaced with 4 standard edges, making the puzzle harder. It was mass-produced by Mèffert's in 2010,^[11] and was also copied by other companies.
• Gear Shift: It was mass-produced by Mèffert's in 2011;^[12] a knock off version also appeared.
• David Gear Cube: Previously called "Polo cube" in reference to Alex Polonsky, who had the idea.^[13] It was mass-produced By Mèffert's in 2013.^[14]
• Geared Mixup: A variant of the gear cube where all faces can perform 90° rotations, allowing centers to be interchanged with edges, hence the term "mixup". It was mass-produced by Mèffert's in 2014.^[15]
• Geared 5×5×5: An unknown Chinese company mass-produced this puzzle in 2015 using a 3D printed sample, without the permission of Oskar. An agreement was met to please both sides.^[16]
• Gear Ball: A mass-produced spherical Gear cube made by Mèffert's.^[17]
• Mosaic cube: Previously called "Fadi cube", it is a corner turning puzzle with two cut depths similar to Okamoto and Greg's "Lattice Cube". It was mass-produced by Mèffert's in 2010.^[18]
• Planets puzzle: Four balls in a frame. Craters on the balls block and unblock movement on the adjacent balls.
• Rob's Pyraminx: It was mass-produced by Mèffert's in 2014.^[19]
• Rob's Octahedron: It was mass-produced by Mèffert's in 2015.^[20]
• Mixup Cube: a 3×3×3 Rubik's cube that can perform 45° rotations on the middle layers, allowing centers interchange with edges. It was mass-produced by WitEden.^[21]
• Treasure chest: A 3×3×3 puzzle that when solved, can be opened, revealing a small chamber inside. It was mass-produced by Mèffert's.^[22]
• Icosaix: A face turning icosahedron with jumbling movements. It was mass-produced by MF8 in 2015.^[23]
• Crazy Comet: Was mass-produced by LanLan without Oskar's permission in 2016 but a deal was archived later.^[24]
• Redi Cube: A corner turning puzzle mass produced by Moyu in 2017.^[25]