Evergreen refers to keywords that are able to be used in any set.
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They are not thematically tied to a block by story or types of races, so can be printed on a wide variety of cards.
Many of these keywords each featured early in the game's history in the Beginner's Block (with the exception of Saver.)
Some later keywords appeared that were soon featured in the majority sets after their release.
As the older keywords were strongly associated with civilizations (Light: 'Blocker', Darkness: 'Slayer', Fire: 'Speed Attacker'), these civilizations help balance this fact (Water: 'Justdiver', Nature: 'Mach Fighter').
'Guardman' appears in the Fire and Nature civilizations as a weaker form of 'Blocker', appearing in the 3 other monocolored civilizations.
Guard Strike(When you add this CARD TYPE from your shield zone to your hand, you may reveal it to your opponent and choose one of your opponent's creatures. That creature can't attack this turn.)