A Sorrowful Blow「悲しき一撃 Kanashiki Ichigeki」 is the 276th chapter of the manga, Nanatsu no Taizai.
The battle begins, Derieri explains to Elizabeth that all Derieri wants was to live for Monspeet, so she wants to end the Holy War. Derieri then risks her life in her plan to extract the commandments from Mael, but Tarmiel stops his attack on him and Mael uses Kyusai no Ya, piercing Derieri's last heart.
Q304. Goat Sin-san: Tell me Gowther's favourite technique or the one that you consider scary.
Nakaba: It would be Search Light that exposes whatever that's hidden.