Mass Detonation is an Advanced Powercard in Bloons Card Storm, introduced in version 3.0. It deals 120 damage to the Bloon with the most health on the opponent's side and 30 damage to the Bloons before and after it in the opponent's Bloon queue, then repeats this effect two times. It can select a different target on each hit. Only one Mass Detonation can be in the Collection.
Players who tend to not regularly use Bloontonium but need to save Gold may greatly benefit from a last-ditch defense with the Mass Destruction.
Mass Detonation is extremely powerful in Aggro, as it allows the Aggro player to attack while also providing very high damage for defense. Keep in mind that drawing Mass Detonation in Aggro is not as likely as other cards, due to the luck needed to draw the single copy of it in your deck.
This card has a high Bloontonium requirement, and most Heroes need to frequently spend on Bloontonium to fuel defense or aggression. It's a strong card for Aggro decks, but less so for OTK and control decks.
In faster and more aggressive Tempo decks, Mass Detonation is used as a way to deal very high damage to an opponent’s board without having to use Gold for defense.
Mass Detonation's effectiveness against 1-delay Bloons can be hindered somewhat if there's a slow high-health Bloon like a MOAB, but against a crowd of 1-delay Bloons like Yellow Bloon it's very efficient.
This card does not deal "splash damage" in the same way as cards with the Splash Damage keyword, such as the Triple Shot and Frag Bomb Shooter. This card was added to the game before the Splash Damage keyword was introduced in version 4.0.
Damage per explosion reduced ― 150 + 50 Splash → 120 + 30 Splash 
Now displays the Splash Damage keyword
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Mass Detonation on a MOAB with one neighbor
Mass Detonation on a Double Rainbow with both neighbors
