The engine has been worked on since version 2.2 (2016) and the focus has been on improving playing style without loss of strength and goals are accomplished and it is expected version 2.8 even is somewhat stronger than 2.2, approximately 5-10 elo as a result.
Sleepy, Sloppy and Stupid are 3 new worked on challenging personalities.
Sleepy is a brilliant edoch arrogant GM who prefers to party late in the night instead of prepare himself for the next game in the tournament against you the next morning, overestimating his capabilities. He will play a strong game against you, reach a favorable position and in his arrogance loses interest because you are such a lousy chess player, gets bored and the lack of a good night rest gets the upperhand and he gets sleepy, starts to play inaccurately. And herein lies your chance, get him!
Sloppy on the other hand is an adorable person you will have to play in the same tournament and honestly you are without chance. However Sloppy also has a specific weakness, he is in love with another player, the lovely female GM Slappy. When your game starts his head is still in the Slappy universe, plays sloppy and you soon will get a won position. Then when Sloppy returns to Earth and notice the hopeless situation on the board he starts to fight back. Your goal, taste the sweet of victory.
Stupid after a brilliant chess career has given up his Morphy style of play and now is a materialist or bean counter, counting wood only, uses no chess knowledge any longer except for the (as he calls) it the PST (Piece Square Technology) which tables he stole from a chess program with the name ProDeo. Fascinated by the progress chess programs have made he is now a firm believer of search only with no chess lnowledge, the zero approach. That's why Sleepy, Sloppy have given him the name Stupid.
Also invited to the tournament was the computer chess program ProDeo 2.6.
After playing 90 rounds the final standing.
Maybe the zero chess knowledge of Stupid is not so stupid after all, he convingly beat both Sleepy and Sloppy with 25/30 and 23.5/30 and Stupid might be your thoughest opponent.