My kids L-O-V-E Doug dug.
My 8yr old wants to know if you can add a tunnel feature. Tunnel would appear at far right or left side of the screen, and upon entering you are faced with 3 tunnel options - left, right, or straight. Arrow points, you choose and then you reappear randomly say 50 meters above or 150 meters below point where you entered tunnel. Or, you may find a cave or chamber with chest of goodies, room full of monsters, or a dead end.
Honk_For_Gronk about Doug dug.