While grinding in Victory Road, I encountered a Horde of Geodude containing one Shiny. This may have been the most nerve-wrecking experience of my entire Pokémon career (Magnitude). Normally Shiny Geodude are a problem because they can Self-Destruct, but luckily the ones in Hordes do not know that move. I couldn't throw any balls until the other four were killed, though. I first thought about just using Surf and see if it had Sturdy, but that was too risky (Geodude can also have Rock Head) and I had an underleveled Venipede in the first spot so I'd have to switch out anyway. I sent out Seabubble, my level 100 Blastoise, just to faint them one by one. In the turn that I switched, the panic already began. The Geodude in the middle used Magnitude, and it got a 7. This put all the others down to approximately half. The other ones all attacked only Seabubble. I used Ice Beam to get the Geodude that used Magnitude down, since it was most dangerous at full health. I was just relaxing a bit that turn, when suddenly this text appeared:
The wild Geodude used Magnitude! Magnitude 6!
I didn't know if my Shiny would be able to survive this, so I got to the tip of my chair again. Then I realized it was the Shiny Geodude that had used the move. The Geodude at the far right fainted (bad Special Defense IVs I guess). In the next turn I got to take out the Geodude left at the middle right. The last one left (at the far left) decided he would leave his special brother to me and attacked Seabubble at last. I threw a Dusk Ball and caught my Shiny Geodude.