I am in a playgroup that only plays casual EDH.
A few months back I decided I wanted to play a chaos deck. The idea sounded hilarious to me, and when looking at potential colours I settled on Britain, with Narset, Enlightened Master at the helm. (I know it’s a CEDH potential commander, but I find it much more fun to cheat out a Shared Fate than a Beacon of Tomorrow!)
Anyway, this is halfway through the pandemic, and finally I get a chance to play this deck in person as the restrictions over here eased a little.
In our very first game I have a Hive Mind on the field, and my opponent (playing a landfall deck) plays Nahiri’s Lithoforming, where X is all the lands he has.
It was only after we had all declared no responses that we remember the Hive Mind.
That is the only time our playgroup has witnessed an Armageddon effect. And the moment of sudden realisation on everyone’s face was everything I built the deck for - pure comedy! That’s certainly a game I’ll never forget!
I actually did the strangest thing I saw in a game. Opponent had a Spellskite, and I used Mindslaver without the infinite loop while using my mono-blue Tron deck. During the opponent's turn, I targeted something with a spell, then made the opponent pay 2 life to activate Spellskite's ability to redirect the spell onto Spellskite. With the spell still on the stack, I just activated that ability for 2 life a bunch of times until it was lethal.
One FNM I did back in the Zendikar/Scars of Miroddin Standard my opponent accidentally shuffled their hand into their deck, the only person who might have actually seen what cards were in my opponents hand was my friend, who is blind in one eye and about 25% blind in the other. Had to stop the tourney for a bit as about a dozen people chimed in what to do in this case.