The Superior Service Medal, or SSM, is the newest and final medal in NOTD. It was made available during the recent addition of Survival Mode. To earn the medal, simply survive 20 waves, a notification will appear during the start of wave 21. However, to actually pass wave 20, you must defeat Ivax ( he will have no abilities however making it very easy) . Unlike most medals, only surviving players will earn the medal, those who died early will not. After earning the medal, you can simply save and quit, it is not required to continue on until defeat or victory. Unlike most medals,all ranks can be earned in normal survival mode OR nightmare survival mode, much like Combat Action Ribbon.
- Complete 20 Waves in Survival mode (30x)