One commander deck of 100 cards would be in the $1 per card range, so a full deck would cost $100, or maybe a little more if you toss in some tokens
There are a few builds centered around Fires of Invention that don't play very many double-costed spells so it would make sense that Jegantha might do some work there...play it as one of your two spells after your Fires turn and then use all of that mana to activate Kenrith, the Returned King or Cavalier of Flame triggers
Important note: The famous oil slick raised foils come with the Compleat Edition bundle
The most valuable card with Phasing is currently Taniwha, also from Mirage
General general-board accio September 30, 2020, 4:33pm 1 Or perhaps I should say, the scarcest
A reduced checklist provides several advantages for collectors and players: Pulls feel more meaningful Less filler and repetition More consistent box openings A clear and focused set identity Smaller sets with strong demand tend to maintain long term attention, both from collectors building binders and from players looking for specific cards