Can you please post a replay.
Because the way you stated it cannot occur.
You said that they used Lightpulsar to send Mirage and Zahak to the grave. This would be a special summon and you cannot special summon except by Xyz during the turn you want to use Message in a bottle.
Also you stated Turn 1 and by Turn 1 they could not have all those cards in a normal duel unless you changed the draw setting before hand.
Anyway I tested this myself, with different cards, and it takes away the 4000 life points just fine.
So if you could please post a replay of this not actually occurring that would be great.
Edited by user
| Reason: Not specified