Making a 10/10 difficulty Killer Sudoku easier

[RealRuler]

3:11 - Why must it be 8+1 - doesn't 3+6, the other pair of numbers in the cells, also equal 9???

[andyp]

This doesn’t make it easier… it’s just watching someone do a hard sudoku quite fast.

[jakeharrison]

At 3:11 how did you work out that in column 4 it was going to be 8, 1 to total 9 when 3, 6 totals nine and that was also available in that column?

[nomasprime]

Shortly after 2:22 I don't understand why the box in the 10 must be 2/3. Can someone please explain this to me?

[kieranwalsh]

@3.13, 6-3 is also an option at that stage, don't see how he automatically assumed 8-1 was the only option

[jeffbrunton]

The 5689 in the top left box could have had the 5 eliminated early on which would have allowed other simplifications

[bigpops]

Wow. I've been having a crack at the 1/10 difficulty puzzles, and IF I can do them without hints, they take me 1-2 hours.

[wilcentng]

some of the level 10/10 puzzles are much easier to solve than those with a lower difficulty

[jagmarz]

I actually just finished this puzzle (in something approaching 2 hours of not-contiguous time) and was really struggling until I noticed that that 11 from the upper boxes of the 17 & 28 cages at the bottom right couldn't be 4+7, and that meant that either the 17 or the 28 cage had both 4+7 and this resolved the lower right 11 to 3+8. From there it fell apart, but it took a loooong time to spot that constriction on 4+7 in the bottom right corner.

[BPP]

2:10 I don't understand 38 and must be 1, 2, 4.

[samanshilevich]

I'm looking for some help on solving some "EVIL" puzzles, is there a community to help with that?