The fourth OVA episode "Anglerfish War!" "Ankō Wō!" (アンコウ ウォー ! ) is a special episode aired on April 24, 2013. It likely takes place chronologically during the events of Episode 10.
The episode features the members of the Ooarai Sensha-dō club performing the Anglerfish Dance in various locations around Ooarai.
- The Anglerfish Dance is a reference to Episode 4.
- There is no ending sequence with the Chibi tank crews or the theme, 'Enter Enter MISSION' at the end of this episode. Instead there is only a credits roll to the instrumental tune of the Anglerfish Dance.
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"School Ship War!"
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