Since arbitrary names can be used for ability tags,

use [dummy] for the feeding ability instead.

data/core/macros/abilities.cfg

@@ -469,12 +469,12 @@ Enemy units cannot see this unit while it is in deep water, except if they have
     # [abilities] clause.  Note: this is deliberately unbalanced WML,
     # in order to close the abilities clause then insert the event
     # then reopen the abilities clause.
-        [heals]
+        [dummy]
             id=feeding
             name= _ "feeding"
             description=_ "Feeding:
 This unit gains 1 hitpoint added to its maximum whenever it kills a living unit."
-        [/heals]
+        [/dummy]
     [/abilities]
     [event]
         name=die