Update on May 7

[h3]Content Updates[/h3]

Optimized some firing sound effects for US light weapons.
Added a new tutorial level to Battlefield mode, including explanations of attack/defense objectives, upgrades and shop, stages, final assault, etc.
Added a new level to Battlefield mode to replace the original level "Flames Of War"; the original "Flames Of War" level has been renamed "War Rekindled", with the same difficulty but some changes to historical presets.
Improved the experience of the "Manor Of Blood" stage in Battlefield mode.
When playing as the defender in Battlefield mode, players will now see attack direction warnings.
The price increase per level for the "Corruption" challenge has been reduced from 50% to 25%.
Optimized the display of the tickets bar when the attackers launch their final attack in Battlefield mode.
Defense missions in Campaign mode will now show attack direction warnings on the minimap.
Language selection panel will pop up on first game launch; if a non-Chinese language is selected, voice lines will be turned off by default.
Added refresh rate setting (now separated from resolution settings).

[h3]Bug Fixes[/h3]