add steadfast ring, reduces knockback when equipped

Items/magic_rings.asm

@@ -0,0 +1,28 @@
+; =========================================================
+; Magic Rings
+
+; Power     - Attack Up, Defense Down
+; Armor     - Defense Up, Attack Down
+
+; Steadfast - Less knockback
+MagicRing_CheckForSteadfast:
+{
+  LDA.l MAGICRINGS : AND.b #$08 : BEQ +
+    STZ.b LinkRecoilX
+    STZ.b LinkRecoilY
+  +
+  #_07E1BE: STZ.b $67
+
+  #_07E1C0: LDY.b #$08
+
+  RTL
+}
+
+pushpc
+org $07E1BE
+  JSL MagicRing_CheckForSteadfast
+pullpc
+
+; Light     - Sword beam at -2 hearts
+; Blast     - Bomb Damage up
+; Heart     - Slowly regenerate hearts