Yeah that's the unfortunate thing with trying to complete the dex for older games these days. If you missed the event(s) for the event-only Pokemon, then you're screwed when it comes to those. The only time I have ever completed the National Dex was on my Pearl, but in that case I had to use an Action Replay to get an Arceus and Shaymin (and probably a few others like Mew or something) to have all 493 registered as caught, as this was years after Diamond/Pearl's release. So like, it was completed, but not 100% legally.I'd love to be able to complete the Gen 4 dex too but it's not possible for me without cheating.