Strategy Games
Seventeen strategy games, and tower defence accounts for most of them. Expect games you can pause and think about rather than games that test your reactions.
All 17 games run in a browser tab with nothing to install.
Tower defence dominates
Nine of the games here are tower defence in some form: Kingdom Rush Frontiers, Fantasy Tower Defense, Hero Rush Tower Defense, Crown Defense, Stick Guys Defense, Neighborhood Defense, Super Mario Defense, Kingdom Attack and Kingdom Battle 3D. The genre has always suited browsers, because it needs no reaction speed and a round can be paused at any point.
The core decision in every one of them is the same: spend now on a cheap tower that helps immediately, or save for an expensive one that will matter in five waves. Getting that balance right is the whole game, and the games that are worth playing are the ones that keep making the choice difficult.
Kingdom Rush Frontiers
Kingdom Rush Frontiers is the best game in this category and one of the best on the site. It is a commercial-quality tower defence game with four distinct tower types, each with two upgrade paths, plus heroes you control directly and abilities on a cooldown.
What separates it from the rest is that its levels are designed rather than generated. Each map has a specific problem to solve, and the solution is usually a particular arrangement of towers rather than simply building more of the strongest one. It is worth playing properly rather than in five-minute bursts.
Where to start
Start with Kingdom Rush Frontiers if you have time, and Fantasy Tower Defense if you do not. Fantasy Tower Defense is the more approachable of the two and gets you to the interesting decisions faster.
State.io Wars and Conquer Kingdoms are a different shape entirely. Both are territory games where you send proportions of your forces between nodes, and both play out in a couple of minutes. They are the quickest strategy games here and the easiest to learn.
Battle simulators
Battle Simulator, War Simulator and Age of Battle put the strategy entirely in the setup. You choose and place your units, then watch the fight resolve without being able to intervene. Whether that is satisfying depends on how much you enjoy being proved right or wrong by something you cannot correct.
One thing filed in the wrong place
Pizza Tower is listed in this category and is not a strategy game at all. It is a fast, expressive platformer with a combo system, and it is one of the better games on the site. If you came here for tower defence you can safely skip it, and if you came here at random it is worth the detour.