Here's why:
* Synchro Summoning Basics: Synchro Summoning requires you to use Tuner monsters and Non-Tuner monsters whose levels add up to the level of the Synchro Monster you want to summon.
* Level Restrictions: All monsters have a level, which is a numerical value that influences their summoning requirements. Levels are typically positive integers, starting from 1.
* No Negative Levels: There are no monsters with negative levels in the Yu-Gi-Oh! TCG or OCG.
Possible Misunderstanding:
You might be thinking of something like a "Level -8" monster. This could be a typo or a misunderstanding of some card effects.
If you have a specific card in mind, please provide the card name, and I can help clarify how it works.