The cards that may cost money will have silver (uncommon), gold (rare), or orange (mythic rare) symbols
They add a unique layer of strategy to the game and lead to some really cool interactionsespecially in decks that focus on long-term value or combo setups
The Ozolith is another good support card, because its a one-mana Artifact that reads, Whenever a creature you control leaves the battlefield, if it had counters on it, put those counters on The Ozolith
Pym Particles Yes, there are some Standard decks for a while now that play a lot of 1-mana cantrips to buff a single creature or two
And you can see up to 12 month's worth of value and pricing history including the current market value of whatever you're buying, which means you can make solid and well-informed buying decisions
The first MtG set that contained holofoil cards was Urzas Legazy, released February 15 1999