A dogtag is the official name for the identification tags worn by S.C.O.T.C.H. agents, because of their resemblance to actual dogtags worn on pets' collars or harnesses.
The dogtag is occasionally being dropped as ghost loot by:
Aliens and UFOS
Hidden treasures is a vulnerability bonus that an agent sometimes receives when trapping certain ghosts with specific trap mechanism types. You can gain a special bonus by using a mechanism of that type to catch such a ghost. Dogtag can be that special bonus.
When you assist a friend by clicking on their ghost monster, you have a chance to receive the dogtags as assist loot.
You can buy various items in Lady Ayumi Bayoushi's shop with the dogtags:
Certain items in Bayoushi's shop also require dogtags as a part of the required currency:
Mechanisms and magic circles
Dogtags cannot be sold, traded or given away.
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