Buff

A buff (symbol: ) is a term that's used to describe the strengthening of something, either through updating a game or by releasing a sequel. Buffs are often done to improve the performance of a tower, by strengthening towers that are considered too weak. The opposite of a Buff is a "Nerf," which involves the weakening of something between sequel games and game updates.

Notable examples

BTD5 Flash to BTD5 Mobile and similar mobile games

• Absolute Zero ability can now slow down MOAB-class bloons, allowing a useful alternative or even combination to the Sabotage Supply Lines.
• In the Mobile versions of the games, an unexpected exploit appears where certain projectiles could duplicate under the influence of Monkey Fort, making projectiles much stronger than before (most noticeable with Glaive Riccochet and Hydra Rocket Pods).
• Dart Monkey Darts have a much larger hitbox in mobile which noticeably improves their overall defending capabilities (especially with Triple Darts which can easily pop 3 layers at a time thanks to this).
• Bloon Impact and Flash Bomb stuns bloons for much longer, making both upgrades more reliable at defending large bloon rushes.

BTD Battles Mobile game updates

• Update 4.6's large series of buffs to the Heli Pilot made it significantly more useful and reliable against defending all types of bloons, thus making it more popular in non-club arenas. Most notably is the immense buff to the Razor Rotors upgrade, having its total cost to get up being slashed by a grand total of $650.
• The Mortar Tower was not nearly used as much compared to BTD Battles Flash due to the smaller explosions it created. However in Update 4.1 the blast radius size was increased significantly, as well as the tower getting some pretty large price cuts to some of its upgrades (most notably The Big One and Artillery Battery), drastically improving its role as a support tower and allowing it to become one of the most used towers in the game as well as opening up a lot of viable loadouts that use the Mortar Tower (most notably Ninja Farm Mortar).
• In Version 4.1, a large number of price buffs to the Ninja Monkey, particularly to the Double Shot upgrade, has made Ninja Monkey a lot more reliable for early-game grouped-popping power. This is particularly true when used against Grouped Blues and above. Despite Version 4.6 and Version 4.9 nerfing the price of both Double Shot and Bloonjitsu, overall, the Ninja has become a lot more reliable in the early-game.