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This doesn't seem like a particularly fulfilling challenge to me. If you were to do it properly, it would just be a hideous grind-fest to get every Pokemon you've caught up to a useable level. As it stands, you just seem to be playing through normally, leaving weak Pokemon in the PC instead of...
If you have access to the GTS, you can take part in the Magnemite loop to get visitors quickly. Otherwise, you get a few people wandering through every day any way, which I would imagine has the same effect, only slower.
I didn't decide until I'd already accepted a place for a different subject, so I'd say you're doing pretty well if you've got it all sorted out a year in advance.
Whichever two of PPE you choose to do at A level, there's going to be one you're not studying for a qualification. This doesn't matter, provided you can still demonstrate an interest in the third, e.g. by off-syllabus reading. So just pick the two you'd be happiest to study at A level and maybe...
Filming somebody having sex, without their consent, and broadcasting it on the internet is not a harmless prank by any stretch of the imagination. That he attempted a repeat two days later is fairly malicious.
I have no idea where you're going with this unless you're going to suggest that Zyklon B was in some way supernatural, in which case you're probably better off not elaborating.