Square Blue

Square Blue is the first Defense in ScrapTD and unlocked by default.

Strategical use
Square Blue seems rather slow compared to Gatling Gun, but their bullets deal the same damage. The only good use of Square Blue is before the second Defense can be brought. It's suggested to spawn Circle Blue at the beginning until this defense is purchasable, then just place two on the field and they should be able to beat the first barrel. With 4 or 5 of them they should be able to beat Square Pink too if they aren't underleveled. When Banana Hole appears, Square Blue gets rather useless.

Surprisingly, Square Blue on levels 15-20 can one-shot Circle Blue on levels 1-6, depending on the defence's level. But it isn't really that neccesary in the higher arenas, since more opponents will have it high up on level.

Overall use
Square Blue albeit is always necessary for the early game, players will mostly get at least 2-4 of them to defend Circle Blue and Square Pink so you can keep Ecoing with the two aforesaid barrels until you can afford Gatling Gun. So hence why it's always used is because you need the early defences necessary or else you may just play very boldly, dangerously or perilously if you don't have this defence on your board.

The ability "Defence Removal" always prioritizes over the defence hierarchy from the weakest defences to the strongest defences, starting at this defence that we have listed.

Trivia

 * Schrottii gave the name "Square Blue", inspired by the first barrel, Circle Blue.