Heavy Drops

Heavy Drops are a type of loot that can be dropped from certain opponents.

Unlike normal loot, heavy versions can't be collected manually and you must have a Collector do it for you. Also, there are blimps and towers (e.g the NOMS that can create heavy loot on the go).

The main feature behind heavy loot is that many bloons/blimps (and things that don't fit into those categories) are capable of collecting these and equipping them due to the fact that many of these are still functioning on their own. Bloons or blimps with the most defencive properties/collection influence* will get priorities the majority of the time when it comes to whom is it collects the drop (if 2 of the same thing is competing for the same part the one closest to the part will receive it.

The range in which a bloon or blimp can collect parts grows as their part capacity does. (Some bloons or blimps can have things that influence this directly).

Monkeys and the likes aren't able to use the vast majority of parts themselves (although Modular M.D.S.s are exceptions, they can directly use them in the same way a bloon or blimp would). However they can be crafted into more useful things (by both you and them...).

* Collection influence is a modifier that can be raised by systems designed to collect parts.

Bloon/Blimp capacities. (How many normal sized heavy parts they can hold at once)
All BTD5 bloons: 1

M.O.A.B: 4

BFB: 7

ZOMG: 10

NOMS: 5

Infestor 3

Infestation 8