>>25047282Dragon typing because lizards mean dragons in Pokéverse for the most part
Lightningrod kind of makes sense when you think of the motif of the Hoenn Starter Megas. They all have to do with speed one way or another.
Speed Boost, self explanatory, Swift Swim increases speed in rain, and Lightningrod + Grass typing makes M-Sceptile virtually immune to Paralysis, a status that reduces your speed.