I'll post some endgame diagrams, starting off easy, mate in two:

Sorry I made a mistake in the diagram, the white bishop is on g1 not c1.

with the bishop on g1, I like 1. Nf6

The threat is simply Bg1-c5-f8-g7#. Black's only defense is to promote the f-pawn with check. So:

1. Nf6 f3 2. Bc5 f2 3. Bxf2

White still  the threat of Bc5-f8-g7# and this time there is nothing black can do about it.

Yeah, agree, and that plan works with the Bishop on c1 as well

Oops, I totally missed that the knight on f6 would be blocking the check from the promoting pawn on f1. So there is no need for white to go back and take on f2 as I had it. Just 1. Nf6 f3 2. Bc5 f2 3. Bf8 4. f1=Q 5. Bg7#

Ok, another one, mate in 6, anyway you will just play 5 moves:

Should I change title?

I don't think mate in 6 is forced in that diagram. How about 1. ... Rxf7 or 4. ... Rxe7.

1. Nxf7  Rxf7   what is white doing next?  if 2. e6 Qxb2 and black's attack is kaput.

I agree, for it to be a mate in x puzzle it needs to be forced in that many moves, not just winning easily. Even right at the end could black not play Qb2 and prolong the agony for quite a bit longer? Perhaps as showing a nice combo in a game, but as a puzzle it doesn't quite work.

Qxb2 in the second one. What do u have now? :)

Hope I dont have flu, mid year exam next weak, try this one, mate in 6 :

In the last one, 3.Qf6 is faster. 3...Rh6 4.Qxg7#, and otherwise 4.Qf8#.

Mate in 7, look in move list for alternate moves.

emtofaan, it doesn't bother you that every single puzzle you've given in this thread has been wrong?

Kh6 looks like a really strong first move for the last puzzle, trapping the king in the corner while white advances his two pawns. Haven't really looked at it too hard but maybe it is mate in 4.

Kh6 Rf6+ Kg4 Rf8 repeats the position, so Kh6 doesn't make progress.

But in the solution line, 5. Qg8# is mate

Well, after reading the comments about all the puzzles being flawed, I didn't look too hard, plugged it into problemiste, It finds 4 different mates in 5, startng with Kg6, or Kh6, or Ng7 or c7

Ah, I missed Kh6 Rf6 Ng6+ and now either Kg8 Ne7# is mate immediately or Rxg6+ Kxg6 and promote a pawn for mate.