World 2 (Super Mario Run)

World 2 is the second world in Super Mario Run. It is the only free world, and completing it unlocks World 3.
==Levels==
=== Ghost-Door Deception ===
A ghost house level that introduces the player to Doors which can be used to travel between rooms.
=== Sky-High Lifts and Leaps! ===
A sky level that introduces line-controlled platforms.
=== Treasure-Hoarding Swoops ===
An underground level with many Swoopers.
=== Airship Cannons...Fire! ===
An airship level containing Ninjis and Cannons, as well as the game's second boss battle, against Boom Boom.
==Enemies introduced==
*Stretches
*Boos
*Bullet Bills
*Swoopers
*Cannonballs
*Ninjis
*Boom Boom (boss)