Whenever you tap a Marsh for energy, add (Black) to your energy pool. Card text uses 「湿地] (shicchi) for "Swamp" instead of 「沼」(numa), which is used in the official Japanese translation of MtG. "Mana" is also changed to the more generic "Energy" here.

Creature

Catacomb Phantom The official translation for MtG's Crypt Ghast is 「墓所の怪異」(Bosho no Kai'i). The creature's name has been deliberately changed here, to 「地下墓場の怪人」(Chikahakaba no Kaijin). Both the name and the following card text are from WataMote Ep 8. Yep, it's definitely MtG with the serial numbers filed off.