Setup Bloon is a Basic Blooncard in Bloons Card Storm. If it hits the opponent's Hero, it reduces the Gold cost of a random Bloon in the player's hand by 1. It has a Delay of 0, so it will attack the opponent at the end of the same turn it's played on under normal circumstances.
As the name implies, the Setup Bloon's primary purpose is to set up a Bloon push on a later turn by reducing their cost.
Since it reduces the cost of all charges, it is efficient at discounting Swarm Bloons and Discount Bloons.
It can reduce the cost of expensive Bloons to allow the player to play more Bloons in a single turn, though there are more reliable ways of bypassing the 20 Gold limit, such as Quincy Action Figures.
With Zee Jay's Passive Awesomeness or Ceramic Glazing Kiln, this card deals comparable damage to Bloon Strike, while still being cheaper and granting a discount. Although this is a fair use for it, the damage is still low and may make it a low value inclusion in burn decks.
Description changed ― On Leaked: Reduce cost of a random Bloon in your hand by 1 → On Leak: Reduce cost of a random Bloon in your hand by 1 (undocumented)