During a summer vacation at my dad's house in Fjerritslev, I got obsessed with doing a 1-credit completion of the arcade version (MVS) of Metal Slug. I trained so hard, I could reliably reach the last level, but always died at the final boss. Now I have a more realistic goal, namely completing the console version (AES), which has 3 credits and adjustable difficulty.
Old edits on my wiki indicate that I was playing a lot of MAME games in 2004, including Metal Slug, which came highly recommended by fellow retro-gamer Yngve. I loved Metal Slug for its fast and precise action and glorious graphics and animation.