[@Mistress Dizzy] Age ranges from 13~18 years old. 

[@GypsyDangerZone] The tiers of Noble Arms are determined by the number of military countermeasures available against it. For example, a Noble Arm that simply strengthens the user is considered low tier because it can be neutralized by a number of factors, while a Noble Arm that can shoot lasers is considered a high tier one because of the lack of countermeasures against it.