Kyoukaisenjou no Horizon Special  

境界線上のホライゾン 完全新作アニメーション「境界線上のホライゾンXXI-PV」, Horizon In the Middle of Nowhere Special, Horizon in the Middle of Nowhere XXI-PV

The Blu-ray Box set of Kyoukaisenjou no Horizon is slated to have an "all-new bonus animation." (Source: ANN)