The combination of searching up a specific card and circumventing its mana cost is the devastating one-two punch on several unfair Magic cards (see Tinker and Stoneforge Mystic)
It was the last time you had an amazingly aggressive first turn Dark Ritual combo until 2005, when it was resurrected in Ninth Edition, but by then Dark Ritual was in the past
Most of them are cheaper cards that are priced at $0.10 or less due to their lack of general playability
Now, if you have a Skyclave Apparition or similar card that can exile the Sun-Crowned, thats definitely worth bringing in for games two and three
Yidris's deck here is compelling as a strong addition to these decks, and that year of power additions to the game
And when you do manage to gang up and kill him, it's not like the Commander tax on a 3 mana leader is overly prohibitive to replaying Leo