Here is a ‘KRRBB vs krbb’ #3 chess construct composed autonomously by the prototype computer program, Chesthetica, using the relatively new computational creativity approach called the ‘DSNS’. Chesthetica is able to generate mates in 3, mates in 4, mates in 5, study-like constructs and also compose problems using specific combinations of pieces fed into it (e.g. instructing it to compose something using a queen, rook and bishop vs. queen and two knights). Read more about it on ChessBase. Any chess position over 7 pieces could not possibly have been derived from an endgame tablebase which today is limited to 7 pieces.
B7/6b1/1k1K4/5R2/R7/1b6/8/4Br2 w – – 0 1
White to Play and Mate in 3
Chesthetica v11.20 (Selangor, Malaysia)
Generated on 12 May 2019 at 6:29:11 AM
Solvability Estimate = Difficult
Chesthetica composes everything autonomously (no human intervention) and even chooses the main line of the solution to show you. Why not time yourself how long it took you to solve this? Solving chess puzzles like this can also help improve your game.
Main Line of the Solution (Skip to 0:35)
Chesthetica 