Ok thank you!

I did those "extremely tough puzzles"

# Original toughest known

Code:

000070940070090005300005070087400100463080000000007080800700000700000028050268000

# Top1465 #2

Code:

708000300000201000500000000040000026300080000000100090090600004000070500000000000

# Top1465 #77

Code:

700000400020070080003008009000500300060020090001007006000300900030040060009001005

And it took:

0.273221 seconds.

12.261032 seconds.

1.838146 seconds

And then..

Reverse bug:

#Reversed BUG digits 2 & 9 in starting grid (example by RW)

Code:

000070502000001060040560310012000609000000103009000420081040730050700000006038000

0.064081 seconds.

#1 column-box interaction for digit 2 (2 candidates locked)

Code:

000907300080065040000000009060040015100000002540090080200000000090250070006408000

0.210432 seconds.

# Uniqueness test 2

Code:

000610000003000500095000078000004005042030760800500000410000620009000300000096000

0.040599 seconds.

# No solution, box with no candidates for a digit

Code:

090300001000080046000000800405060030003275600060010904001000000580020000200007060

Contradiction in 0.027824 seconds.

Is there anything special that I should try to see how good my solver is compared to others? I can ofc do those puzzles that you posted but there were no problem to solve them, atleast not the ones (and only) I tried. SO should I cuntinue or do you guys have something special hidden?