Spike is a pet that was added in Update 10. It is a black pet with spikes coming out of it. Since Update 10, the stats are random. It has about a 30% chance of hatching. Its rarity is 3 stars.
The stats will most likely range from 350,000 to 400,000, for most players. Of course, there will be some exceeding the range, but this is so far the most likely one.
Spike certainly has no reskins, the only other versions are Spike, Golden Spike, Rainbow Spike, and Dark Matter Spike.
Golden, Rainbow, and Dark Matter
When converted to Gold, Spike can be level 1,050,000 to 1,200,000, when converted to Rainbow, Spike can be level 2,100,000 to 2,400,000 (when hatched rainbow Spike can be from 2,450,000 to 2,800,000), and Dark Matter Spike can be level 6,300,000 to 7,200,000.