Magic Online Society's website and Discord are good places to start down the player-run-events path, and Cardhoarder maintains a list of them as well, although I'm not sure all of the events listed are still active
TheChirurgeon: Gilgamesh fits the "honorable warrior" archetype - he follows Exdeath but after Galuf is killed in a heroic sacrifice, Gilgamesh loses his appetite for what was previously fun, nonlethal clashes with your party
2 Ultimate Magic: Meteor/Ultimate Magic: Holy The Ending And The New Beginning Sephiroth succeeds in summoning Meteor, and we watch as death and destruction plague all of Gaia
Pair Nasty End with Ringwraiths, Gollum, Patient Plotter, or best of all, Haunt of the Dead Marshes, and watch your hand grow while your opponent despairs
The fuse mechanic, introduced in Dragon's Maze , is just the entwine mechanic applied to split cards (the ability was called "splitwine" in design)