Return to Answer

Indeed, there are many possible positions in which all mates are forced on the first ply. Since you ask not for that, I shall provide examples with more than one move by both sides.

Here is the known, and overall, length record for both sides having multiple legal moves since you said that a single line "isn't too satisfying."

[Title "Alexey Khanyan, Tim Krabbe's Website Diary Entry #267 2008, Mate In 11 Moves/22 Plies"]
[FEN "4Q2Q/4r3/4n1n1/1bbK1krn/RR1RR1RR/2qn1R1n/4n1nN/Q3Q3 b - - 0 1"]
[startflipped ""]

1... Ng2f4+ 2. Rfxf4+ N2xf4+ 3. Rgxf4+ Nh3xf4+ 4. Rhxf4+ Ndxf4+ 5. Rxf4+ Nhxf4+ 6. Rxf4+ Ngxf4+ 7. Rxf4+ Nxf4+ 8. Rxf4+ Kxf4+ 9. Qee5+ Qxe5+ 10. Qaxe5+ Rgxe5+ 11. Qxe5+ Rxe5+ 12. Qxe5#

Source: Diary Entry #267

Additionally, I know of this simple problem that illustrates it with either playing giving mate.

[Title "Eugene B. Cook, The Chess Amateur 1926, Mate In For White And Black"]
[FEN "Bk6/1P6/1P3p2/8/8/2P3p1/6p1/6Kb w - - 0 1"]

Lastly, be sure to check out a funny mutual zugzwang position in this CSE question by the user @Peter, in which both sides are forced to let the other mate them!

Indeed, there are many possible positions in which all mates are forced on the first ply. Since you ask not for that, I shall provide examples with more than one move by both sides.

Here is the known, and overall, length record for both sides having multiple legal moves since you said that a single line "isn't too satisfying."

[Title "Alexey Khanyan, Tim Krabbe's Website Diary Entry #267 2008, Mate In 11 Moves/22 Plies"]
[FEN "4Q2Q/4r3/4n1n1/1bbK1krn/RR1RR1RR/2qn1R1n/4n1nN/Q3Q3 b - - 0 1"]
[startflipped ""]

1... Ng2f4+ 2. Rfxf4+ N2xf4+ 3. Rgxf4+ Nh3xf4+ 4. Rhxf4+ Ndxf4+ 5. Rxf4+ Nhxf4+ 6. Rxf4+ Ngxf4+ 7. Rxf4+ Nxf4+ 8. Rxf4+ Kxf4+ 9. Qee5+ Qxe5+ 10. Qaxe5+ Rgxe5+ 11. Qxe5+ Rxe5+ 12. Qxe5#

Source: Diary Entry #267

Additionally, I know of this simple problem that illustrates it with either player giving mate.

[Title "Eugene B. Cook, The Chess Amateur 1926, Mate In For White And Black"]
[FEN "Bk6/1P6/1P3p2/8/8/2P3p1/6p1/6Kb w - - 0 1"]

Lastly, be sure to check out a funny mutual zugzwang position in this CSE question by the user @Peter, in which both sides are forced to let the other mate them!

Indeed, there are many possible positions in which all mates are forced on the first ply. Since you ask not for that, I shall provide examples with more than one move by both sides.

Here is the known, and overall, length record for both sides having multiple legal moves since you said that a single line "isn't too satisfying."

[Title "Alexey Khanyan, Tim Krabbe Website Diary Entry #267 2008, Mate In 11 Moves/22 Plies"]
[FEN "4Q2Q/4r3/4n1n1/1bbK1krn/RR1RR1RR/2qn1R1n/4n1nN/Q3Q3 b - - 0 1"]
[startflipped ""]

1... Ng2f4+ 2. Rfxf4+ N2xf4+ 3. Rgxf4+ Nh3xf4+ 4. Rhxf4+ Ndxf4+ 5. Rxf4+ Nhxf4+ 6. Rxf4+ Ngxf4+ 7. Rxf4+ Nxf4+ 8. Rxf4+ Kxf4+ 9. Qee5+ Qxe5+ 10. Qaxe5+ Rgxe5+ 11. Qxe5+ Rxe5+ 12. Qxe5#

Source: Journal Entry #267

Additionally, I know of this simple problem that illustrates it with either playing giving mate.

[Title "Eugene B. Cook, The Chess Amateur 1926, Mate In For White And Black"]
[FEN "Bk6/1P6/1P3p2/8/8/2P3p1/6p1/6Kb w - - 0 1"]

Lastly, be sure to check out a funny mutual zugzwang position in this CSE question by the user @Peter, in which both sides are forced to let the other mate them!

Indeed, there are many possible positions in which all mates are forced on the first ply. Since you ask not for that, I shall provide examples with more than one move by both sides.

Here is the known, and overall, length record for both sides having multiple legal moves since you said that a single line "isn't too satisfying."

[Title "Alexey Khanyan, Tim Krabbe's Website Diary Entry #267 2008, Mate In 11 Moves/22 Plies"]
[FEN "4Q2Q/4r3/4n1n1/1bbK1krn/RR1RR1RR/2qn1R1n/4n1nN/Q3Q3 b - - 0 1"]
[startflipped ""]

1... Ng2f4+ 2. Rfxf4+ N2xf4+ 3. Rgxf4+ Nh3xf4+ 4. Rhxf4+ Ndxf4+ 5. Rxf4+ Nhxf4+ 6. Rxf4+ Ngxf4+ 7. Rxf4+ Nxf4+ 8. Rxf4+ Kxf4+ 9. Qee5+ Qxe5+ 10. Qaxe5+ Rgxe5+ 11. Qxe5+ Rxe5+ 12. Qxe5#

Source: Diary Entry #267

Additionally, I know of this simple problem that illustrates it with either playing giving mate.

[Title "Eugene B. Cook, The Chess Amateur 1926, Mate In For White And Black"]
[FEN "Bk6/1P6/1P3p2/8/8/2P3p1/6p1/6Kb w - - 0 1"]

Lastly, be sure to check out a funny mutual zugzwang position in this CSE question by the user @Peter, in which both sides are forced to let the other mate them!

Indeed, there are many possible [positions](https://puzzling.stackexchange.com/questions/30409/highest-number-of-mates/87225#87225_ in which all mates are forced on the first ply. Since you ask not for that, I shall provide examples with more than one move by both sides.

Here is the known, and overall, length record for both sides having multiple legal moves since you said that a single line "isn't too satisfying."

[Title "Alexey Khanyan, Tim Krabbe Website Diary Entry #267 2008, Mate In 11 Moves/22 Plies"]
[FEN "4Q2Q/4r3/4n1n1/1bbK1krn/RR1RR1RR/2qn1R1n/4n1nN/Q3Q3 b - - 0 1"]
[startflipped ""]

1... Ng2f4+ 2. Rfxf4+ N2xf4+ 3. Rgxf4+ Nh3xf4+ 4. Rhxf4+ Ndxf4+ 5. Rxf4+ Nhxf4+ 6. Rxf4+ Ngxf4+ 7. Rxf4+ Nxf4+ 8. Rxf4+ Kxf4+ 9. Qee5+ Qxe5+ 10. Qaxe5+ Rgxe5+ 11. Qxe5+ Rxe5+ 12. Qxe5#

Source: Journal Entry #267

Additionally, I know of this simple problem that illustrates it with either playing giving mate.

[Title "Eugene B. Cook, The Chess Amateur 1926, Mate In For White And Black"]
[FEN "Bk6/1P6/1P3p2/8/8/2P3p1/6p1/6Kb w - - 0 1"]

Lastly, be sure to check out a funny mutual zugzwang position in this CSE question by the user @Peter, in which both sides are forced to let the other mate them!

Indeed, there are many possible positions in which all mates are forced on the first ply. Since you ask not for that, I shall provide examples with more than one move by both sides.

Here is the known, and overall, length record for both sides having multiple legal moves since you said that a single line "isn't too satisfying."

[Title "Alexey Khanyan, Tim Krabbe Website Diary Entry #267 2008, Mate In 11 Moves/22 Plies"]
[FEN "4Q2Q/4r3/4n1n1/1bbK1krn/RR1RR1RR/2qn1R1n/4n1nN/Q3Q3 b - - 0 1"]
[startflipped ""]

1... Ng2f4+ 2. Rfxf4+ N2xf4+ 3. Rgxf4+ Nh3xf4+ 4. Rhxf4+ Ndxf4+ 5. Rxf4+ Nhxf4+ 6. Rxf4+ Ngxf4+ 7. Rxf4+ Nxf4+ 8. Rxf4+ Kxf4+ 9. Qee5+ Qxe5+ 10. Qaxe5+ Rgxe5+ 11. Qxe5+ Rxe5+ 12. Qxe5#

Source: Journal Entry #267

Additionally, I know of this simple problem that illustrates it with either playing giving mate.

[Title "Eugene B. Cook, The Chess Amateur 1926, Mate In For White And Black"]
[FEN "Bk6/1P6/1P3p2/8/8/2P3p1/6p1/6Kb w - - 0 1"]

Lastly, be sure to check out a funny mutual zugzwang position in this CSE question by the user @Peter, in which both sides are forced to let the other mate them!