I wasted my Master Ball on a Farfetch'd! (Gameplay mistakes)

Hmm... let's go back to a nine year old me...

In Pearl, which was my first game, catching a Shinx and overleveling it. Like, seriously overleveling it. By the time I was facing the E4, I had my Luxray (level 60-75?) and five other Legendary Pokémon just to survive because I had not trained any other Pokémon but my Luxray.

Also in Pearl, I used my Master Ball on Uxie. At the time, it wasn't staying in any of my other balls so great decision, but now I look upon that and think that if I had been a lot more patient I'd still have my Master Ball.

Oh, and screaming at Giratina when I first saw it. Shut my DS off and lost some progress...

 

Where do I start...
Trying my hardest (for like, a solid 15 minutes) to go up steps. Doesn't seem like a problem, does it? Well, the problem was that those steps were actually ledges. Yes.
Derping and forgetting to charge my DS before receiving a Lvl. 91 Chansey through WT. RIP Chansey.
'Wait, you can CATCH other Trainer's Pokémon?!' -9 year old, really gullible me.
'So, I saw this cool red dragon show up in my game and fainted it' -Playing Silver before I realized what I had done. And I had FRICKING SAVED RIP RED GYARADOS!
Ha ha, more like FAILED it. Ha ha ha HA HA HA VERY FRICKING FUNNY
'What does 'Release' do?' No more needs to be said, other than RIP Lvl 89 Breloom
#MissingNo.

 

For me it was battling Virizion in W2. Decided to weaken it a little bit more- with Golbat and using Fly. After I used Fly I remembered that flying is super effective against grass and fighting. So R.I.P. Virizion. On a positive note Golbat evolved into Crobat after defeating Virizion.

 

I still do. Like, I'll be inside a Center in Sun and try calling Tauros. I do it WAY too often.
#MissIngNo

 

I usually tried calling Charizard in Pokémon Centers XD