[Guido]

Originally Posted by KoiYuki

Yuno wrote scripts for him to act on, so that explains the personality change somewhat... He also went through a bunch of traumatic experiences until eventually the straw that broke the camel's back came along (his parents deaths) and he realized that he needs to win, or else not only is he dead, but so is everyone else that's already died (his parents, the other diary holders, countless innocent civilians, etc). He wants to revive everyone, but he can only do that by winning.

So basically, he ended up really broken, but still wants to fix things, and you can't win a murder game by hesitating. Yuno and him probably figured out that the kids would come after them too, so they'd have to take them out (why get more targets placed on yourself than necessary?). I'm gonna say it's safe to assume that Yukki probably was against it, but she convinced him that he could just revive them anyway and that it was the only way.

No idea about the driving at all though.

Even if I haven't watched the twenty-first episode, still I would continue to agree with you.

The twenty-first episode reached a cathartic poignancy for Yukiteru, because Yukki made a point that he never wanted to be involved in any of this and let alone killing. However, Minene counters that one cannot go in life hesitating, being soft, or expecting that everything will turn fine, if your personal situation changes out of the blue and without warning.
She lost her parents in a foreign country where warfare and genocide were the everyday bread; nobody came to save her, she had to learn how to fend off for herself and survive. Her situation forced her to quickly steeled herself up by discarding completely her childhood innocence and start killing in order to survive, nothing else than that.

If something or someone had happened to interfere in a positive light with what happened to her fate, then things might have turned out different for her; I would say 50+/50- probability chance of a better or an even worse fate because the stream of fate and the river of life are flows intertwined carrying uncertainties.
Even if this show has owners using Diaries that can predict their futures for the survival game, the diary themselves only tell them- "Because I acted upon this, I averted myself from getting killed"- and not this- "Because I choose to follow this set course of actions, I kill all the others and became God for a better life."

Minene, at last, was able to empathize with Yukiteru at a very personal level, because she saw her childhood self in him, and I feel seriously bad for Minene holding an illusory hope that she might be alive somewhere, and for Yuki because he truly intends to amend his selfishness once becoming God and reviving absolutely everyone starting with his parents.

Spoiler:

Now, the thing is that Deus lifespan has finally reached its end, but the curious note is that Murumuru is alarmed that he's dying one week ahead from schedule, and she sounds as if either she expected Deus to die at the specific date of July 28th or has known beforehand the end of Deus lifespan because she herself has witnessed it before.

Now, I understand why this show always displays the date and exact time, because it tells to the audience that's the countdown to that world's doom.

But, that's not all of it, and lots of you haven't slip that tiny detail off their minds.

Last episode, I theorized Murumuru was secretly working with Eleventh, but that theory crumble to dust after Yuno killed Eleventh, and we have only three Diary owners: Yuki, Yuno, and Eighth.
Is out of the question that Yuki is Murumuru's secret employer for the single reason that he was thrown and caught off guard by the game since from the beginning.

I don't see any reason why Eighth would team up with Murumuru to plot against Deus from behind-the-scenes, because Eighth is not the type to be interested at all to become God; for her the orphans were her most precious and world to her.

The only one left is Yuno, and I have evidence that she has to be Murumuru's co-plotter: Early in the first episodes, Yuno always mentioned to Yukki that they'll come together, and she was referring to an exact date, remember?

And, that date is July the 28th, the date that presumedly Deus life will come to an end, according to Murumuru. However, Deus's dying ahead of time, which is putting in jeopardy whatever plan Murumuru and Yuno have been cooking up.
Also, in the closing shot that ends the episode, Yuno's face lets out an expression as if hinting to the audience that Yuki must not find out, or her plans for Yuki are now put in serious jeopardy.

The other evidence lies about the identity of the skull being Gasai Yuno herself, and Akise concluding the current Yuno is a fake one which is confirmed further by the Eleventh due that the door to the second vault could only be opened by him, Yunos' parents, and her via retina scan. However, for a twisted surprise, Yuno was able to open the second door with no problem.

If the current Yuno is a fake one, how could her scanned DNA enabled her to open the door?

Spoiler for Wild Theory:

The reason could be because the current Yuno is actually Gasai Yuno herself, and I don't buy she might be Yuno's estranged and long-lost twin sister.

She's not an impersonator either.

She is GASAI YUNO!!!