Quick Scoop

You likely mean Spike in Blox Fruits , not a “spike collar.” Spike is a common fruit you can get from the Blox Fruit Dealer for 7,500 Beli , or by buying the permanent version for 75 Robux ; if it is not in stock, you need to wait for the dealer refresh or trade for it.

How to get it

  1. Go to the Blox Fruit Dealer in the game.
  1. Check whether Spike is currently in stock.
  1. Buy it with Beli if available, or buy the permanent version with Robux.
  1. If it is not stocked, keep checking back after the dealer rotates stock, or trade with another player.

What the sources say

Spike is listed as a Common Natural-type Blox Fruit and is sold by the dealer for 180000 or 380 on one wiki page, but another current trade-value page says it costs 7,500 Beli and 75 R$ for perm Spike.

Because those figures conflict, the safest answer is to use the in-game dealer price you see right now, since stock and pricing info can vary by source and update timing.

Practical tip

If you are trying to get it fast, server-hop or recheck dealer stock until it appears, since Spike is a low-tier fruit and can be easy to miss in rotation.

TL;DR

Spike is usually obtained by buying it from the Blox Fruit Dealer, purchasing the permanent version, or trading for it.