Harmony (ハーモニー Hāmonī) is a keyword found on SIGNI introduced in WXDi-P02 CHANGING DIVA.
| Harmony [number] [color] LRIGs (Whenever this SIGNI enters the field, down it unless you down [number] of your upped [color] LRIGs.) |
Whenever a SIGNI with Harmony enters the field, you must down a specified number of LRIGs, often LRIGs of certain colors; otherwise, the SIGNI is downed and thus cannot attack that turn. While this ability triggers when the SIGNI enters the field, it is not an 
ability and thus still triggers even if the SIGNI enters the field with an ability that states "Its abilities don't activate."
SIGNi with Harmony tend to be powerful level 3 SR-rarity SIGNI. Harmony encourages players to play those SIGNI in decks of both the SIGNI's color and the color specified in its Harmony ability. As the abilities of some LRIGs require you to down a number of assist LRIGs to use their effects, a Harmony ability can also prevent you from using those. Harmony also discourages you from playing multiple Harmony SIGNI in the same turn. As Harmony is a drawback ability, SIGNI with Harmony tend to be more powerful in exchange.
