A Flagpole (also known as a Goal Pole) is an object found at the end of most levels in Mushroom Kingdom Fusion. It originates from the original Super Mario Bros game and if the player touches the Flagpole in any way, they clear the level. The higher the player reaches the Flagpole, the more points they receive, which the top of the Flagpole earning the player with a 1up. Most enemies on-screen will also be instantly defeated after the Flagpole is touched.
Most levels with boss fights don't feature a Flagpole at the end as the level ends after the boss is defeated. Some of the levels that don't feature a boss at the end use an alternative to the Flagpole. For example, most levels in World 7: Isle of Genesis use the Goal Plate (which turns from an image of Dr. Eggman to an image of the character the player has selected) instead as they are based on the Sonic series.