Gaining and losing abilities
An ability can be added to a card by an ability that says: <card> gains "<ability text>". The target <card> is treated as if is has the additional ability printed on it in a separate paragraph in the text.
Only keyword abilities can be removed. This is because without a keyword there is no simple way to match which ability should be removed.
An keyword ability can be removed from a card by an ability that says: <card> losses <keyword>