Either navigate to the snapshots gallery from the main menu and choose Sabre Wulf, or choose Sabre Wulf from the game gallery, and select snap shots.
Choose snapshot 1 and navigate through the game, killing everything you see by hitting
or
to earn points. Also pick up any gems or other collectibles for additional points. Once you get 5000 points you can stop or just keep going. I got it on my second attempt, but I’m not very good at these games so you’ll likely get it first try.