Fantasticar is a transportation car created by Mr. Fantastic.
It is shown as being able to travel from New York to Siberia in a matter of minutes on autopilot, and can be summoned from Reed's palm top computer. Like its comics counterpart, it can also split into multiple sections (only three in this version).
In an element of product placement, the Fantasticar has the Dodge logo (presumably inspired by the Juggernaut meme) on its front end, prompting Johnny to ask if it is powered by a Hemi. ("Of course.")