Ok I have to say this first Kurono is a coward for making the decision he did and a complete ahole. Can I really mean this but of course I can and I will tell you why.
Letís start with the fact that now his mug is plastered all over TV and if the vampires/aliens/demons (damn there a lot of things Iím going to call them VADs) can easily track him down and kill him now. Worse yet they can use him to
trap his friends and kill them because he now has no memory he wonít know whatís going on and have no real way of defending himself.
Now for the people he didnít revive even though he agonized over it what happened? Did he think that if he revived one he would have to revive the other? Did he think they couldnít survive the game and it would be a waste? One thing for sure in order to not care he chose to have his mind wiped such a weak thing to do.
Abandonment of friend even when he could clearly see that Gantz is giving increasingly dangerous mission and they just survived the last one even Izumi was inspired by him to keep fighting when he had obviously lost hope of wining saving all there lives (whether Izumi was inspired by not wanting to fall behind him or by his determination I donít care). This is by fare the worst of the thing he did by choosing selection 1. Without him I wonder how far their survival rate just drop if and when they get an even harder mission then the last one.
Finally He was the sum of his experience sure he has that feeling to survive when he was a kid but now he is back to that jack ass that he was before he entered Gantz missions. That as we saw when he thought it was funny that people died and that Tokyo got ripped up when he saw it reported on TV and was totally indifferent to it.
Conclusion in sort he ran away from his memories because he didnít want to feel the weight of them (coward no other word exist for him). Next now that Gantz has chosen not to hide his presents anymore he might see himself fighting on TV but most definitely the VADs will track him down so it was like committing suicide. Not only that but people not involved with Gantz are killing indiscriminately all the time he had a better survival rate within Gantz. So he must want to die is the only conclusion left to me very sad and Iím so disappointed in this outcome.
Yes I think the time limit and the hiding of his people was to mask his present mostly from the VADs. Once they started showing themselves and remarked about Gantz the strongest of Aliens being on the move he no longer needed to do these things. Also I believe he really wanted the VAD he sent them out to kill dead and he wouldnít have died because the timer would have run out if he chose to keep it going. Iím not sure want Gantz motive are but he is making the human race defend itself from invasion but he seems to have fun doing it. Who knows he may be the biggest threat to the world and just want the others out of his way.