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Several rounds of airship usage also taught the whole world a lesson: the correct use of expensive war machines is the key to gaining an advantage; wrong command, in turn, can only waste high-tech equipment that comes at a hefty price.
At the same time, countries also witnessed the formidable strength of multi-layered trench defense systems bolstered by powerful artillery firepower.
These defenses effectively helped the outnumbered Songmu Kingdom withstand the powerful attack from Poplar Kingdom while also significantly reducing losses and preserving their fighting force.
Especially, the permanent defenses constructed of concrete were like killing machines fixed on the battlefield, with countless bunkers functioning like the blades of a meat grinder, devouring the flesh and blood of attackers.
After fighting for three days with no progress and realizing that they could not break through the border defenses, the Poplar Kingdom had no choice but to change their tactics.
