Down (ダウン daun), represented by the symbol in costs, is the state a LRIG or SIGNI is in on the field when it is landscape-oriented (turned sideways). It is the opposite of being upped.
LRIG or SIGNI are not downed by default; rather, LRIGs and SIGNIs become downed whenever they attack. Some LRIGs and SIGNI have abilities with costs that require them to be downed, such as Mandore, Natural Plant, and certain card abilities can also cause SIGNI to be downed, such as the ability of Don't Move. Cards that are downed before they attack cannot attack.
When a LRIG or SIGNI is downed, it cannot be downed again until it is upped first.