literally unpossible puzzle on lichess

https://lichess.org/training/O3Hxm

i'm being genuine this time. i have NO clue whatsoever how i was supposed to find Nd4. i would probably play it in a real game because its funny but how am i supposed to calculate that its objectively the best move? the engine thinks its +5 but i have no idea how i could've figured that out

The idea is to remove the queen so then you can play qf5 , qh5 mate . Really hard to see all the variation from the initial position

Nd4 in the final position is to remove the black queen from defending the f5 square. Once it moves, then white plays Qf5 and threatens Qh5+ with a common checkmating pattern.

thanks, i get it now. to the 200 people i accidentally notified you don't have to click on the puzzle, just assume its gm level