If my Nessian Demolok resolves, there's nothing anybody can do to stop the Choose an opponent part. There's no way to stop me from choosing an opponent at this point, and there's no way for that opponent to get out of making a choice
Alternative Art Gardevoir is currently running for around 60 (or $60 to $70 ) as of release
Are only a small number of cards in the deck going to get you to the win, or can just about any combination push you there
It did take another few years afterwards, but by 2021 we were officially seeing new cards with phasing show up over multiple standard sets
The final dragon, Crosis, appears when the other four sacrifice themselves in an Urborg Tar-Pit, but he resurrects them and the Primevals begin destroying everything in their path, Phyrexian or otherwise
Its difficult to get your hands on for under $100, but its definitely not unheard of