Got two, neither especially clever but both were effectively game ending (one for me and one for an Opp).
Finally got around to grinding out at least gold constructed rank before the season reset earlier. Figured mono-R was the path of least resistance and grabbed Seth Manfield's deck from Worlds. Only have two Cleaves and don't care to craft another, so I sub in a single
Claim the Firstborn for gotcha potential. Game to jump into gold is the mirror, on the draw but have an ok hand. Opp gets out quickly with Fervent into Robber into Anax. I have my own Anax on 3 and Opp passes back on 4 without much event. Lo and behold, here comes Claim to save the day. Swipe my Opp's Anax and bin it to legend rule, giving me four 1/1s and one less Anax on Opp's side for a single R. Opp conceded before I could Cleave the following turn.
Was playing Historic Brawl with
Dovin, Grand Arbiter against an Opp on
Ayara, First of Locthwain. I got out early with a
Mist-Cloaked Herald with
Staggering Insight that mercifully wasn't killed before I had counterspells up. Opp played Ayara into
Underworld Dreams into
Spawn of Mayhem before I eventually countered some dorky big B creature with
Essence Scatter. Opp is down to 4 while I'm at 20, waiting to untap to win. They play Gary at X=
14, which I conveniently have no counterspells left for. I'm able to get them back down to 5 and go back up to 7 on my turn, but it's not enough to make up for that giant swing.