User blog:The Primordial Clok-Roo/BATTD: A New Undiscovered Secret...

Actually, I don't know if this secret really IS undiscovered, but it's not mentioned here on the Wiki, so I'm just going to assume it is. So I was just doing one of the Bloon Beaon challenges in BATTD, when I accidentally discovered something incredible! There is a hidden, secret synergy between Supermonkey and Captain Cassie. And it's actually really REALLY good!

How it works is simple:
 * 1) Place Supermonkey in range of Captain Cassie. You may want to farm for cash using stuff like Finn and Jake's Brofist upgrade, BMO, and so on, because you will need a LOT of money for this.
 * 2) Upgrade Captain Cassie to Bloon Pillage (requires Captain Cassie to be Level 5), and Supermonkey to Sun Avatar.
 * 3) Select Captain Cassie. You will notice that a new upgrade that was never there before has now appeared named Treasure Hunter. The description will read 'Cassie loots Sun Avatar Idols for extra cash.'
 * 4) Simply purchase this upgrade - price estimate at around $2500 - and you will unlock a secret achievement of the same name and a special end of round ability where Captain Cassie will generate a handful of Sun Avatar Idols that each give $350.
 * 5) Play the game and do stuff.
 * 6) Profit.

I should mention that I also had the Dark Temple Idol equipped on Supermoenky, so I don't know if that's a part of the pre-requisits or not.

I also haven't added this information directly to the relevant pages in fear of it being treated as vandalism and removed, given how sudden this discovery might come across as. I'm posting this blog with everything that needs to be done here so that others can test it and verify it.

But I promise you, this is 100% legit!

Other things that should be noted about this upgrade:
 * Even after it has been purchased, this upgrade does not permanently reveal itself on Captain Cassie's upgrade tree once you exit/complete the level; it only shows up for that level as long as you are playing it.
 * The achievement reward is one Rare wish orb, and the icon is a Supermonkey statuette, similar to the ones you use to level up Supermonkey
 * This upgrade does not appear to have a context-specific quote, similar to the Privateer upgrade.