Using the same scenario, let's now consider that initially, there were actually 4, not 2 dragons playing in the field, but then 1 of them decided to leave and go back to its lair. Later, 4 other dragons saw the remaining dragons playing in the field and wanted to join them, but they still needed to leave the dragons in their lair by subtracting the number of dragons that were already playing in the field. How many dragons now had to leave their lair to join the playing dragons?