I've just finished Bored89-Easy. Nice puzzle!
It is easy but only after one finds the key move. It appears from the earlier messages that some people didn't find it. I must admit that I was also struggling until I spotted step 3a.
I wasn't sure how to rate this puzzle. Step 3a isn't a difficult move but it's hard to spot unless one is looking for that sort of move. Obviously I can't take into account the time "wasted" before that step so I'll rate Bored89-Easy as a 1.25.
Here is my walkthrough.
Thanks Afmob for your comments which I've used for editing several steps. Fortunately my error in step 8 didn't affect other steps; that elimination is now made in step 26c.
This is a Killer-X. I've included eliminations along diagonals, for those not using software to do eliminations, because they are easy to overlook.
Prelims
a) R3C56 = {89}, locked for R3 and N2
b) R45C6= {14/23}
c) R45C7 = {59/68}
d) R56C3 = {18/27/36/45}, no 9
e) R56C4 = {16/25} (cannot be {34} which clashes with R45C6)
f) R7C45 = {49/58/67}, no 1,2,3
g) R456C5 = {289/379/469/478/568}, no 1
1. Killer pair 1,2 in R45C6 and R56C4, locked for N5
2. 45 rule on R12 2 outies R3C37 = 7 = {16/25/34}, no 7
3. 45 rule on R89 2 outies R7C37 = 3 = {12}, locked for R7
3a. CPE no 1,2 in R3C37, clean-up: no 5,6 in R3C37 (step 2)
3b. Naked pair {34} in R3C37, locked for R3
3c. CPE no 3,4 in R5C5
4. 15(3) cage at R3C1 = {159/168/258/267/357/456} (cannot be {249/348} because 3,4,8,9 only in R4C1
4a. 8,9 of {159/168} must be in R3C12 -> no 1 in R4C1
4b. 3,4,8,9 of {159/258/357/456} must be in R4C1 -> no 5 in R4C1
5. 13(3) cage at R3C8 = {157/247/256} (cannot be {139/148/238/346} because 3,4,8,9 only in R4C9), no 3,8,9
6. 45 rule on N1 2 outies R2C4 + R4C1 = 9 = [18]/{27/36}/[54], no 9, no 4 in R2C4
7. 45 rule on N3 2 outies R2C6 + R4C9 = 11 = {47/56}, no 1,2,3
8. 45 rule on N7 2 outies R6C1 + R8C4 = 10 = {19/28/37/46}
/[55]
[I first made a "doubles possible" error more than a year ago. Since then I've usually managed to avoid that error so I don't know why I made it this time. I think that every time I've noticed "doubles possible" for outies they have been eliminated before the final solution. Maybe sometime there will be a puzzle with this "trap" using the doubles as part of the final solution. ]
9. 45 rule on N9 2 outies R6C9 + R8C6 = 9 = {18/27/36/45}, no 9
10. 45 rule on N4 3 innies R4C13 + R6C1 = 11 = {128/137/146/236/245}, no 9, clean-up: no 1 in R8C4 (step 8)
11. 45 rule on C6789 3 innies R139C6 = 20 = {389/479/569/578}, no 1,2
11a. 3 of {389} must be in R1C6 -> no 3 in R9C6
12. 45 rule on N5 2 innies R4C4 + R6C6 = 14 = {59/68}
13. 7 in N5 locked in R456C5, locked for C5, clean-up: no 6 in R7C4
13a. R456C5 = {379/478}, no 5,6
14. Killer pair 8,9 in R3C5 and R456C5, locked for C5, clean-up: no 4,5 in R7C4
15. 45 rule on C1234 3 innies R179C4 = 16 = {169/178/259/268/349/358/367/457}
15a. 9 of {169/259/349} must be in R7C4 -> no 9 in R9C4
16. Hidden killer pair 1,2 in R45C6 and R8C6
for C6 -> R8C6 = {12}
16a. 45 rule on C789 2 outies R28C6 = 1 innie R6C7 + 5
16b. Max R28C6 = 9 -> max R6C7 = 4
16c. R28C6 = 6,7,8,9 = [51/52/61/62/71/72] (cannot be [42] which clash with R45C6), no 4, clean-up: R6C9 = {78} (step 9), no 7 in R4C9 (step 7)
17. 45 rule on N6 3 innies R4C9 + R6C79 = 15 = {168/267/348/357} (cannot be {456} because R6C9 only contains 7,8, cannot be {258} which clashes with R45C7)
17a. 3 of {348} must be in R6C7 -> no 4 in R6C7
18. R7C7 + R8C6 = {12} = 3 -> R8C78 = 16 = {79}, locked for R8 and N9, clean-up: no 1,3 in R6C1 (step 8)
18a. CPE no 1,2 in R8C9
19. Killer triple 7,8,9 in R4C4 + R6C6, R5C5 and R8C8, locked for D\
20. 15(3) cage at R6C6 = {168/249/258/267/348/357} (cannot be {159} which clashes with R139C6, cannot be {456} because R6C7 only contains 1,2,3)
20a. 9 of {249} must be in R6C6 -> no 9 in R7C6
20b. 3 of {348/357} must be in R6C7 -> no 3 in R7C6
21. 45 rule on N8 3 innies R7C6 + R8C46 = 15 = {168/258/267} (cannot be {348/357/456} because R8C6 only contains 1,2), no 3,4, clean-up: no 6,7 in R6C1 (step 8)
21a. 2 of {258/267} must be in R8C6 -> no 2 in R8C4, clean-up: no 8 in R6C1 (step 8)
22. Hidden killer pair 3,4 in R19C6 and R45C6
for C6 -> R19C6 must contain 3 or 4 -> R139C6 (step 11) = {389/479}, no 5,6, 9 locked for C6, clean-up: no 5 in R4C4 (step 12)
23. 15(3) cage at R6C6 (step 20) = {168/258/267/357}
23a. Hidden killer pair 5,6 in R2C6 and R67C6
for C6 -> R2C6 = {56}, clean-up: no 4 in R4C9 (step 7)
24. 13(3) cage at R3C8 (step 5) = {157/256}, CPE no 5 in R12C9
25. R4C9 + R6C79 (step 17) = {168/267/357}
25a. Killer pair 5,6 in R45C7 and R4C9 + R6C79, locked for N6
26. 45 rule on N2 3 innies R2C46 + R3C4 = 13 = {157/256}, no 3, 5 locked for N2, clean-up: no 6 in R4C1 (step 6)
26a. 6 in {256} must be in R2C6
(R23C4 cannot be {26} which clashes with R56C4) -> no 6 in R23C4, clean-up: no 3 in R4C1 (step 6)
26b. Killer pair 1,2 in R23C4 and R56C4, locked for C4
26c. 5 in C5 locked in R789C5, locked for N8
27. R4C13 + R6C1 (step 10) = {128/245} (cannot be {137} because R6C1 only contains 2,4, cannot be {146/236} because 1,3,6 only in R4C3), no 3,6,7, 2 locked for N4, clean-up: no 2 in R2C4 (step 6), no 7 in R56C3
27a. 1,5 must be in R4C3 -> R4C3 = {15}
27b. 2 locked in R46C1, locked for C1
28. 14(3) cage at R3C4 = {158/167} (cannot be {257} because 2,7 only in R3C4), no 2,9, clean-up: no 5 in R6C6 (step 12)
29. Naked pair {68} in R4C4 + R6C6, locked for N5 and D\, clean-up: no 4 in R46C5 (step 13a), no 1 in R56C4
30. Naked pair {25} in R56C4, locked for C4 and N5, clean-up: no 4 in R4C1 (step 6), no 3 in R45C6
31. Naked pair {14} in R45C6, locked for C6 -> R8C6 = 2, R7C7 = 1, locked for D\, R7C3 = 2, locked for D/ -> R56C4 = [25], 5 locked for D/, R6C9 = 7 (step 9), clean-up: no 4 in R5C3, no 7 in R19C6 (step 11) -> R1C6 = 3
32. Naked pair {89} in R39C6, locked for C6 -> R67C6 = [67], R6C7 = 2 (step 23), R2C6 = 5, R4C9 = 6 (step 7), R4C4 = 8, R3C4 = 1 (step 28), R4C3 = 5, R2C4 = 7, R7C45 = [94], R9C6 = 8, R3C56 = [89], R89C4 = [63], R1C4 = 4, R1C1 = 5, locked for D\, R46C1 = [24], R45C7 = [95], R8C78 = [79], 9 locked for D\ -> R5C5 = 7, 7 locked for D/, R46C5 = [39], clean-up: no 3 in R5C3
32a. R7C12 = 11 = {38}/[65], no 6 in R7C2
33. Naked pair {67} in R3C12, locked for R3 and N1
33a. Naked pair {25} in R3C89, locked for N3
34. R7C3 + R8C4 = 8 -> R8C23 = 9 = {18}, locked for R8 and N7
and the rest is naked singles, remembering eliminations along the diagonals
5 2 9 4 6 3 8 7 1
1 3 8 7 2 5 4 6 9
7 6 4 1 8 9 3 2 5
2 7 5 8 3 4 9 1 6
8 9 6 2 7 1 5 4 3
4 1 3 5 9 6 2 8 7
6 5 2 9 4 7 1 3 8
3 8 1 6 5 2 7 9 4
9 4 7 3 1 8 6 5 2
I'll have a try at the "Hard" version once I've caught up with a couple of other walkthroughs. A fair number of the steps used for "Easy" can still be used because of the way the puzzle wraps itself around N5.