Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Nc3/3...Nf6/4. Nxe5/4...Nxe5

4...Nxe5
Black accepts the gambit and needs to play with precision, as White will launch an attack with d4, then quick development of the queen and bishop to form pressure on the Black King to overwhelm Black.

For Black to succeed the most, they have to play in a way that undevelops their pieces at first, which seems very strange, but then as White develops their queen, making sure not to lose defense of the b7 pawn by moving their bishop, and pushing back White's threats possibly a turn in advance. Eventually, Black will gain back space and will be able to develop their pieces again.

Theory Table
'''1. e4 e5 2. Nf3 Nc6 3. Nc3 Nf6 4. Nxe5 Nxe5'''