Steely is an achievement which is unlocked by popping 250,000 Lead Bloons in BTD5.

Since there are very few Lead Bloons in regular games, this is unarguably an achievement that I'll take a huge amount of time to get. You'll encounter a total of 277 Lead Bloons in a Hard or Impoppable game.



Replaying the Special Mission "Wizard Lord" is an effective way to receive the achievement, as it has 1,247 Lead Bloons. However, this will still force you to play the mission a total of 201 times... This mission takes roughly 430 seconds to complete. From start (0 popped Lead Bloons) to achievement received, you have to gather 24 hours of playtime on this mission.

Here is my method to make these 201 playthroughs more doable:

Immediately after starting the mission, set the Wizard Lords priorities to "Strong" instead of "First"

Next, spawn 14 Dart Monkeys anywhere on the map. These will act as a sacrifice for the Wizard Lord.

The Wizard Lord will endure all Bloons independently until Round 16 (when MOABs appear). This gives you exactly 210 seconds were you don't need to be involved at the computer, giving you time to concentrate on other things.

When the MOABs starts to appear, simply use the Super Monkey Storm to clear all MOABs. This still counts as popping the lead bloons.

You'll need 11 Super Monkey Storms per mission. This will add up to 2211 SMS's during your 201 missions, costing $110.550. Adding your total reward for the missions makes your total loss at $30.150.

For me, an avid player, a loss of 30k is not a huge loss. If this is an amount you're willing to spend, you should consider this method.