Spiked Mines (BTD5)

"Rigged with heavy explosives, the spiked balls are set to go off when they lose all their spikes."

- BTD5 Official Description

Spiked Mines is the final upgrade for path 1 of the Spike Factory in Bloons TD 5. Each spiked ball can pop up to 16 bloons before exploding. There is a skull on top of the spiked mine production chute, and a skull on top of the mines it produces. This upgrade rigs the spike balls with heavy explosives, causing them to go off when they lose all their spikes, as well as doubling the tower's deployment speed (BTD5 only). The explosion gives bloons a napalm effect, similar to the Mortar Tower's Burny Stuff upgrade. The napalm pops bloons every 2 seconds for 6 seconds. The explosions pop 4 layers.

It costs $14,000 on Medium.

BTD5
It is far more powerful in the Flash series, because of its immense attack speed bonus and overall great damage output. It can even be more useful than MOAB-SHREDR Spikes in that regard. Spiked mines are not suitable for bloon rushes for especially round 49, 53, 61, 62, 63, 65, 69, 70, 78, 79, 82, and 83. This is because the explosions only impact the bloon that is already destroyed by the spikes and no other bloon other than one other bloon will be hit. A spike mine can single handed destroy a ZOMG if put at the end of a long trap so the max number of mines are placed without any buffs.

In the Mobile series, however, it is substantially weaker than the Flash versions, as it doesn't attack as quickly, as well as the fact that mines expired by time expiry do not explode.

Differences Between BTD5 Flash and BTD5 Mobile
Spiked Mines has a slower attack speed (4/1: 1.6 shots per second → 1.42 shots per second; 4/2: 2.67 shots per second → 2 shots per second).

Spiked Mines have smaller explosions and negate the popping power of the Spiked Ball Factory upgrade (each ball pops 16 bloons before exploding instead of 20).

Spiked Mines do not explode when they disappear after time.

Update History (Bloons TD Battles Mobile)
3.1

Spiked Mines price decreased ($14000 → $12000).

Trivia

 * Spiked Mines with Even Faster Production upgrade, Spikes R Us tier 2, and Tack Awesomizer can destroy an entire ZOMG, provided the spike factory is located far enough from the start of the track and the mines are sufficiently concentrated.
 * If the Spiked Mines are not used, they will explode after a while in the same way normal spikes or Spiked Balls disappear after a certain amount of time.
 * This does not happen in BTD5 Mobile.
 * If a Spiked Mine Factory is put into the Socket of Power in "The Crucible", it will produce spiked balls so fast that it appears that the hatch is not moving. This only happens on fast forward, however.
 * The Tier 4 upgrades for the Spike Factory are the last to be unlocked, the second last are the Dartling Gun Tier 4 upgrades, and the third last are the Mortar Tower Tier 4 upgrades, however, it is the third last in BTD5D, followed by the Monkey Engineer and Bloonchipper, respectively.
 * But after the Monkey sub update, it is the third last to be unlocked, as the Monkey Sub's Tier 4 upgrades are the last (on BTD5 Mobile, of course).
 * Spiked Mines' explosions are not powerful enough to pop Black Bloons and Zebra Bloons.
 * It takes 4 4/2 Spiked Mines to pop a Z.O.M.G..
 * It takes however two to pop a ZOMG fully on long, easy, 'one end' track.
 * It takes one only to pop a ZOMG fully in BMC, a long track and only one ending, like the flower grass terrain track, without any support. As seen, the spiked mines upgrade is really useful in capturing tiles in BMC.
 * It only takes one one a really long track, for example monkey lane.
 * It only takes one one a medium length track, given Tack Awesomizer and a level 2 Spike Production Building.