Drill Senki Wiki | Danbooru

A free-to-play RTS that launched in 2016 and ended on November 30, 2016.
You commanded a fleet of cute girls driving combat vehicles.

The game was referred to as Dorisen (ドリセン) for short.
The first two kanji (弩龍) literally translate to "crossbow dragon". Normally these kanji would not be read as "doriru". However, their onyomi would read as "doryuu", which is close.