You may not, for instance, discard Golem-Skin Gauntlets to get a Steel Golem
Yes, while most non-English Magic cards are direct translations, some feature unique alternate artwork, particularly those released for the Japanese market
Summary Mardu decks in Magic: The Gathering combine black, red, and white colors, offering powerful removal spells and value card draw options
There is a WB vampire deck that uses a lot of the Ixalan vampire cards to create a massive, life-draining army of bloodsucking conquistadors
1 The Horus Heresy
These are generally limited to more recent sets, but thats where a lot of people get their start, so its not a bad place at all to build a position