October Mega Cook-Off 2018 Division 2
Ada and the Staircase, Binary Nim 2
December Challenge 2018 Division 1
Max and Electrical Panel, Directing Edges, Chef and Interactive XOR
November Challenge 2018 Division 1
Appy Loves One, Good Median
October Challenge 2018 Division 2
Appy and Balloons , Beautiful Bricks, Minimize Digitsum, Chef and Surprise Chessboard, Chef and Serves, Byte to Bit, Chef and Circles
January Challenge 2019 Division 1
Yet Another Problem About Sequences, A Pizza Slice, Distinct Pairs, Different Neighbours
January Challenge 2020 Division 2
Chef and Dynamo, Doraemon, Doofish Matrix, Equality, Chefina and Prefix Suffix Sums, English, Breaking Bricks
February Challenge 2020 Division 1
Chef and Railway Stations, No Change Required, Long Contest and Cook Off Overlaps
United States