It changes only how you may pay those costs
These retro artifacts arent Standard-legal like the rest of the set, but they are legal in both Draft and Sealed - where theyre often absurdly powerful yet a lot of fun to play with
You choose which player, planeswalker, or battle the creature you put onto the battlefield is attacking as it enters the battlefield
Doubling effects are highly dangerous, because now every pump spell does double damage, and there may even be other things that can double the effect again
Brawl Legal Vintage Legal Timeless Legal Commander Legal Pauper Not Legal Oathbreaker Legal Penny Not Legal Toolbox Buy This Card Notes and Rules Information for Crystal Fragments // Summon: Alexander: Each face of a nonmodal double-faced card has its own set of characteristics: name, types, subtypes, abilities, and so on
If you need more scholarly sources, here are all the MTG card types explained