People get into Narnia via Aslan's choice.

"If God and Aslan are the same, than does God, who is loving, send His children to Hell?" All references to theological query about Narnia are framed within Lewis' own ideas. "There are only two kinds of people in the end: those who say to God, 'Thy will be done,' and those to whom God says, in the end, 'Thy will be done.' All that are in Hell, choose it. Without that self-choice there could be no Hell." -Lewis, The Great Divorce As I noted in the prior round free will is one of the singular most important constructs in the series. Lewis is arguing against predestination (God chooses) and instead argues that peoples decisions in life are ultimately what lead to their downfall (Susan, Jadis, Nikabrik etc.) or their salvation. This is why Calormenes (essentially archetypal Pagans) enter True Narnia. Which leads to another Lewis' theological argument - the types of choices made have as much bearing on the judgement enacted in TLB as does 'belief'. Lewis' characters are set to the virtue/vice dynamic. These archetypes are the means through which Lewis intends to teach his readers. Those who do good deeds in the name of Tash are awarded placement in True Narnia, those who do less than good in the name of Aslan do not enter. Those creatures that are apathetic about belief are judged on that basis as well -Susan the archetype materialist/cynic does not enter True Narnia. Peter who started along the same road (scepticism - he believes he does not need Aslan to win the battle in PC - i.e. without the spirit of Aslan) but regains his lost faith - does enter. Nikabrik the full cynic suffers a less than enviable fate. Polly who retains her faith her whole life enters True Narnia and becomes youthful again (TLB). Another interesting aside - Lewis had strong pagan roots, found he admired pagan spirituality and in many ways held it in higher regard to Christianity. "To become a Christian one must first be a pagan." TCoN are littered with references to pagan traditions - arguably as much as Christianity - he lamented he often prayed like a pagan. ;) He held the same disdain as Tolkien did for the destruction of natural environments - evil characters in both of their series destroy trees with glee abandon. "Does Aslan have His people kills in battle?" Did those who fight for Aslan die? Some did yes - there are several battles between the great beasts throughout the series - Aslan in TLB judges *all* who have died in Narnia meaning those that fell under his banner were awarded entry into True Narnia. "Does Aslan ruin his own country by bringing Jad[i]s in?" Not at all - she is given the chance of redemption after the destruction of Charm. It is through her actions that lead ultimately to her death. Faithful remain even during the endless winter - the type of virtue repeated in PC (a type of virtue Lewis wants to bash into his readers) where the Prince believes wholly in Aslan though all he has are tales. Lucy is the archetypal faithful character, she is the one who is able to enter Narnia initially (childlike faith at that instant) she alone feels the presence of Aslan in CP, she is the first to see him. ""Aslan," said Lucy, "you're bigger." "That is because you are older, little one," answered he. "Not because you are?" "I am not. But every year you grow, you will find me bigger."" As her faith grows so does Aslan. "Does Aslan Plan that man will come and smash the Narnians?" Plan would be predestination which is against what Lewis believed. Aslan introduces necessary elements into Narnia through which individuals may earn their salvation or not. "I don't think Aslan would want himself killed." He does to fulfil the Christian analogy part (and prophecy to become Narnia's saviour). The stone table he is sacrificed upon most likely represents Mosaic law - on the table is written eye for an eye retribution - Jadis has the right to take a life for every act of treason which is why Aslan sacrificed himself (Christ on cross) for the sake of Edmund (archetype sinner/born again). The stone table breaks indicating that this way is no longer valid (transition of OT law into NT teaching). "But if you look at the other side, does it seem more logical that we happen to go to hell by chance that we choose to" According to Lewis it's choice. That is all that is relevant to the debate. "Jad[i]s happened to be touching the horse and everyone else, and taints the new magical land by chance?" Her actions, not chance. The same actions which lead to her death and eventual judgement in TLB. Diggory plants the tree 'copy' from a seed of the Tree of Protection. The copy reacts to events of the Tree of Protection - it moves when the parent tree does (a copy itself). The Tree of Protection dies presumably by actions of Jadis - she cannot approach the tree - so we can assume magic (she did destroy her home world - and the Earth copy tree is destroyed by lightning). Diggory builds the wardrobe from the fallen tree which allows the Penvises to enter. Jadis' persecution of them leads to her eventual death. It's her actions that lead to her downfall - she has the option to not be evil - albeit an even duller narrative would have ensued but that wasn't Lewis' intent at any rate. Her choice of actions fulfils the prophecy of her destruction - that's what Lewis drives at. All Aslan needs is to have those necessary elements should they occasion merit. He *sends* Eustace and Jill into Narnia *specifically* for similar purposes as were the Penvises brought into Narnia. "Nothing ever happens the same way twice" Indicating Aslan's motives behind it all. "Does it seem logical that Aslan would come into our world and opened a door for the people to get in" The creation of Narnia was for the sole purpose of judging both those created as part (the great beasts) and those of other worlds for entry into True Narnia (see TLB, R1).