Negative Level
Negative Levels are a concept appearing only in the Yu-Gi-Oh! 5D's anime, and are used exclusively on the new Dark Synchro Monsters. In real life any such Levels are instead positive.
Currently, the only card that can cause a monster to have a negative Level is "Dark Wave".
They are represented by , which aligns to the left of the card, whereas positive Level Stars align to the right.
Example: