P/T Set Number 361 Language Deutsch Legal Formats Commander, Legacy, Vintage Not Legal Formats Alchemy, Brawl, Competitive Brawl, Historic, Modern, Pauper, Pioneer, Standard, Timeless Rulings (8/25/2017) You draw one card for each Dragon you controlled that attacked, even if some of them left the battlefield before The Ur-Dragon's triggered ability resolves
That's almost the same as just buying the booster packs and doing it manually, and you don't get the incidental commons and uncommons you also need to make a deck work
There will need to be a personal or communal selection of land cards, so that players can build a 40 card deck from the 42 card selection, including extra Land cards to ensure they can power their spells
Second, Korvold can be your Jund commander, and a fairly powerful one at that