Kingdom Rush：Frontiers

Kingdom Rush Frontiers (also known as Royal Guard Frontiers in China) is a fantasy tower defense game developed by Ironhide Game Studio, first released as Flash web game in 2013. It is the second main entry of Kingdom Rush series. Players travel to exotic frontiers including deserts, rainforests and underground caverns. Build defensive towers along enemy paths to stop monster waves and defend the endpoint. It keeps four classic tower types from the original game: archer barracks, melee barracks, mage towers and artillery towers. It adds 8 new advanced tower branches such as Templar, necromancer tower and earthquake machine, with over 18 unique tower abilities. Controllable hero units are newly introduced; heroes move freely on battlefield, cast unique skills and gain levels during combat. There are over 40 enemy types including giant scorpions, gorillas, dragons, pirates, mummies and powerful stage bosses. Global spells like meteor strike, reinforcements and freeze can be activated in emergencies. Multiple difficulty settings, secret stages and challenge modes greatly extend replay value. Hand-drawn cartoon art style, humorous story and smooth combat animation make it one of the best Flash tower defense games, later ported to mobile, Steam and other platforms.

These games get the keyboard directly — the controls are whatever the game itself defines, usually in its own help or options screen. Some games show on-screen buttons on phones.