My evaluation of the stockfish engine here.
The engines are paired off in my opinion. 4 levels with 2 levels each. An easy, and hard level.
Level 1 and 2 have built in automatically lose functions. Level 1... you can basically remove all your pieces in board editor but your queen, and pick off everything they have from there and get a mate without them ever taking your queen unless forced to. I think vs level 1 if I just put all the legal moves into a random number generator and made totally 100% random moves I would beat the machine more often than losing to it. I have actually seen how much it is designed to lose, by winning against it with just a queen from board editor against an entire army...
Level 2: Basically like level 1, but 1/10 of the time it will make a stronger move than level 1 so same thing really.
Levels 1 and 2 are designed for players just learning how the pieces actually move to be honest. No challenge at all even for a beginner.
Level 3... Level 3 is where the computer actually starts to play chess. If you hang your queen here then it will pick it up most of the time. It doesn't attack very well though.
Level 4... Basically level 3, but it attacks a little more, and defends slightly better.
Level 3 and 4 are for beginner players. I would say level 1000-1300 players would have good games vs these
Level 5: Level 5 is for intermediate players, but it's weaker than level 4 in some ways.
Level 6: It's like if levels 5 and 4 put their heads together, and teamed up against you.
Levels 5 and 6 are designed for more intermediate players. They make mistakes but are less obvious about it.
Level 7: This is where it starts to get hard. i can beat level 7, but it's hard.
Level 8: I can rarely beat or draw level 8. Level 8 is like level 7, but with more accuracy... It's really hard for me to fight this beast off.
So...
level 1 and 2 I would beat roughly 100% of the time. No challenge whatsoever
Level 3 I won't ever lose to level 3 either.
Level 4 or 5... I might lose 1 in 20 games vs either of these
Level 6 I would beat level 6 about 9 out of 10 times
Level 7 is where it gets difficult if I played 10 games vs it I might expect to win a few, and draw a few, and lose a few. It's pretty solid...
Level 8 crunks me up I have beaten it rarely, but it's tactical precision is very high, and it don't miss tactics. It also is brutal when it comes to openings... I would say if I played 100 games vs it... It would probably win 80-90 of them I would drop 15-20 of them, and I would win less than a handful of them
