Kamigawa is an expert-level block for the Magic: The Gathering game inspired by Japanese myths and revolving around the battle between spirits (kami) and living beings. It consists of the expansion sets Champions of Kamigawa (October 1, 2004), Betrayers of Kamigawa (February 4, 2005), and Saviors of Kamigawa (June 3, 2005). Set history Champions Champions of Kamigawa introduced changes to two common creature types. The Legend creature type was replaced with the Legendary supertype. The Wall creature type was freed from the associated rules that prevented Walls from attacking; Each Wall creature was changed to have the new Defender keyword which prevents them from attacking, allowing for a simpler use of the "wall" type creature across different creature types. For example, this allowed for the Lorwyn changelings, which have all creature types. Under the old rules, changelings would not be able to attack, through sheer result of being walls. Legend and Wall were the last creature types in Magic to have inherent rules associated with them. The set's expansion symbol is a torii, the entrance to the Shinto temple. This is especially important, as Kamigawa's original idea was summed up as "Shinto gone horribly wrong": Kami warring against their human worshippers. Mechanics Champions of Kamigawa introduced several new mechanics to the game. Some instant or sorcery spells have the Arcane subtype, which represent spells or abilities used by the kami. It does nothing by itself, but other cards may interact with it. One type of spell that can interact with Arcane spells are spells with the keyword "Splice onto Arcane", which can be "attached" to another Arcane spell for additional mana investment. The "spliced" spell remains in the player's hand able to be reused another time. The block contains a large number of Spirit creatures (representative of the kami), some of which were printed with the Soulshift keyword, which allows them to return another Spirit creature from the graveyard to its owner's hand when they perish. Other Spirits have abilities which trigger when another Spirit or an Arcane spell is played. By contrast, many samurai were printed with the Bushido ("way of the warrior") mechanic, which increases a creature's power and toughness by the Bushido number when it combats another creature. (This is usually compared to flanking, which weakens (-1/-1) the blockers of the creature). Certain creatures, nicknamed "heroes", are "flipped" (the card is turned 180 degrees) when particular conditions