Bloons Tower Defense
Monkeys throw darts at balloons. That's it — and it was enough to devour a billion study halls. Bloons Tower Defense loaded in any browser, ran fine on a school computer, and turned "one more round" into the defining lie of 2000s homework time.
New Zealand studio Ninja Kiwi released the first Bloons Tower Defense on August 16, 2007, spinning the tower-defense formula out of its own hit series of dart-throwing Bloons popping games. The setup was instantly legible: waves of balloons — "bloons" — crawl along a path, and you place monkey towers to pop them before they escape. The original shipped with just five towers, from the humble Dart Tower up to the Super Monkey, and that was plenty; the loop of placing, upgrading, and watching a screen fill with popping was self-evidently perfect.
As a free Flash game it spread everywhere embeddable games lived — the game portals, the unblocked-at-school sites, the computer-lab bookmarks — and Ninja Kiwi iterated fast: BTD2 arrived just two months later in October 2007, BTD3 in 2008, BTD4 in 2009, and BTD5 in 2011, each round-tripping between browser and the new smartphone stores. Across web and mobile the series has been played over a billion times.
The franchise then did what almost no Flash-era series managed: it outlived Flash itself. Bloons TD 6, released in 2018, found an enormous new audience on phones and PC storefronts, and in March 2021 Ninja Kiwi was acquired by Sweden's Modern Times Group in a deal worth up to $186 million — a monument to how far a monkey with a dart can travel from a 2007 browser tab.
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