Devotion mechanics (thanks to excessum for patch)

+ some refactoring:
extrManaCost --> ExtraManaCost
unattachCost --> UnattachCost

projects/mtg/bin/Res/sets/primitives/mtg.txt

@@ -37348,6 +37348,16 @@ mana={1}{G}{G}
 type=Enchantment
 [/card]
 [card]
+name=Gray Merchant of Asphodel
+auto=life:-type:manab:mybattlefield opponent && life:type:manab controller
+text=When Gray Merchant of Asphodel enters the battlefield, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)
+mana={3}{B}{B}
+type=Creature
+subtype=Zombie
+power=2
+toughness=4
+[/card]
+[card]
 name=Gray Ogre
 mana={2}{R}
 type=Creature

projects/mtg/bin/Res/test/_tests.txt

@@ -14,6 +14,7 @@ generic/changeling_i501.txt
 generic/cycling.txt
 generic/cycling2.txt
 generic/deathtouch.txt
+generic/devotion.txt
 generic/doesnotuntap.txt
 generic/doesnotuntap2.txt
 generic/double_strike.txt

projects/mtg/bin/Res/test/generic/devotion.txt

@@ -0,0 +1,30 @@
+# Testing Devotion mechanic
+# also checking that hybrid cost and phyrexian cost are handled correctly
+# total devotion should be 2 + 1 + 1 = 4
+
+# Gray Merchant of Asphodel
+# When Gray Merchant of Asphodel enters the battlefield, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)
+
+# Reaper King
+# mana={2W}{2U}{2B}{2R}{2G}
+
+# Vault Skirge
+# mana={1}{p(B)}
+
+[INIT]
+firstmain
+[PLAYER1]
+hand:gray merchant of asphodel
+inplay:Reaper King,Vault Skirge
+manapool:{3}{B}{B}
+[PLAYER2]
+[DO]
+gray merchant of asphodel
+[ASSERT]
+firstmain
+[PLAYER1]
+life:24
+inplay:gray merchant of asphodel,Reaper King,Vault Skirge
+[PLAYER2]
+life:16
+[END]