World 5 (New Super Mario Bros. Wii)

Toxic Forest is the fifth world of New Super Mario Bros. Wii. The levels are all forest themed featuring poisonous water. Bramble vines block some of the paths. hey will occasionally change positions. There are eight levels in this world, two of them being castle levels that are guarded by Iggy Koopa, and one being a Ghost House. Various Mushroom Houses are also found around here, giving the player items such as Starmans, Mushrooms, and Propeller Mushrooms. On the map, there are Stalking Piranha Plants. Mario and the gang can get attacked by and be forced to play in the Enemy Course. There are a total of 3 Enemy Courses in the area. Also, once Iggy has been defeated in the castle, the bramble patches will disappear completely.

5-1
This is the first level in World 5. It introduces the Stalking Piranha Plant and the River Piranha Plant. It contains very large Koopa Shells, some of which, Mario can enter and find secrets. While most of this level takes place on land, a portion of it it over a body of water. There are many swinging vines the player can use to travel over gaps and Stalking Piranha Plants. Fire Mario is very helpful in this level.

World 5 Ghost House
The third ghost house in the game. Common ghost house enemies can be found, including boos. It is possible to find a secret exit that will take Mario and company to the world 5 cannon. This cannon shoots Mario to world 8, Bowser's Volcano.