Fyndhorn Elves, from 1995's Ice Age expansion, is neither incredibly powerful nor incredibly valuable - its original printing has never cost more than a few dollars, and mechanically identical cards exist and only see niche play
If you don't control an Army, create a 0/0 black Orc Army creature token first.) Amass Orcs 2
Here's your mtg card size
Elesh Norn is a 3/5 with vigilance and possesses an ability that says whenever a source an opponent controls deals damage to you or a permanent you control, that sources controller loses two life unless they pay one mana
Keep in mind that deckbuilding checklists are general guidelines to help improve your deck, not strict rules that must be adhered to 100%
You might not have a spell you can play with all that mana or a way to beat a chump block with your infinitely strong creature