Deploy Sub-Tower is an attack style characterized by spawning additional sub-towers as part of a new attack, usually within its range. It is part of the damage types family.
Deploy Sub-Tower is represented on Bloons Wiki as 
, the upgrade icon for Sentry Gun in Bloons TD 6, as this is the core upgrade that demonstrates deploying sub-towers. It is distinct from Spike Pile 
in that the projectile being thrown must have more than one dimension. Spikes do not have more than one dimension, as they are just purely just "lay on the track and affect bloons touching it", and are normally placed directly on the track. Admiral Brickell's mine production attack is tricky to categorize; they are considered Create Sea Mine 
because it is not a spike pile (it is a subset of On-Track 
), and the only two-dimensional aspect of mines is its active graviation towards bloons upon detection of bloons.
Typical examples of Deploy Sub-Tower is the Engineer Monkey's deployment of Sentries, Comanche Defense summoning of mini-Comanches, and high-level Magic Sacrifices Sun Temple's mini-Sun-Avatars.
There are strange interactions for Deploy Sub-Tower when interacting with attack speed buffs such as Jungle Drums. Version 22.0 removes potential for Sun Temple's mini-Avatar deployment attacks to be affected by any sort of attack speed buff. Engineer remains the only one whose interactions with attack speed buffs are affected. Comanche Defense uses a passive ability to activate sub-towers, so attack speed buffs won't do anything to make the mini-Comanches summon any faster.
Most attacks require an upgrade to have the attack style Deploy Sub-Tower.
