Yeah, I've heard Rumble is actually quite fun.
Other than that, Tadreth is correct. I think the Arceus Tin has 2 Arceus, 1 SV and 1 other pack, while the Garchomp tin has 2 SV 1 RR and 1 other one.
I'm not sure. I think it might be Pre PL, but not pre DP (i.e. SF, MT, SW etc.)
I have no idea when Darkash is going to pick his prizes, so I'm just going to list the prizes I want the most to the prizes I want least.
1. Arceus Poster Box
2. Garchomp Lv. X Tin
3. Arceus Lv. X Tin
4. Pokemon Rumble
I'll list mine as well:
1. Garchomp Lv. X Tin
2. Arceus Poster Box
3. Arceus Lv. X Tin
4. Pokemon Rumble