You and your playgroup can use whatever method youd like, though
Its Multiverse contains many planes, some of which, for thematic reasons, want to deviate from the norm in how they name things, including species
It costs one more to cast than Sakura-Tribe Elder / Rampant Growth or Explosive Vegetation - which is a big deal since you really want to be ramping in your early turns so a turn 2 Rampant Growth is way better than a turn 3 Rampant Growth - but offers you the flexibility of which version you want to cast
While scorpions and spiders being treated as something separate, having slug actually be loved enough to continue being represented as a race is pretty fun
He has three strength, which, while low, is still impressive, and seven willpower, which is what makes him the perfect bodyguard
The deck focuses on quickly building a massive army of creatures, growing the army through anthem and counter effects, and attacking for massive damage