In terms of gameplay, a Foil Magic The Gathering card against a regular Magic The Gathering card has no difference
Modal double-faced cards (MDFCs) These are the ones where you choose which face to cast or play (spell on one side, land on the other, etc.)
Jin-Gitaxias, Progress Tyrant Abundance mentality Jin-Gitaxias, Progress Tyrant is a seven-mana mono-Blue 5/5 with a chunk of text: "Whenever you cast an artifact, instant, or sorcery spell, copy that spell
If you're on a tight budget, there's good news waiting if you're okay with damaged cards, as you can pick up a copy for under $20 in most cases
In burn-heavy builds I really like Detonate, as its yet another source of direct damage