Gigabax - 2 Most Similar Forms

The 2 most similar forms of Gigabax, Dark Form (Darkbax) and Bug Form (Bugbax). It's also the debut picture for Darkbax & Bugbax, meaning the first time they've been shown.

Similarities:
Their headgear, the Giga Helmets, are very similar.
They are both thin, although Darkbax's skin is bone tight.
They both have 2 claws on each foot.
They both have large teeth that stick out of their mouths when closed.
They both have long necks and thick heads.
They both have an 'overlapping' top lip.

Differences:
Colours.
Number of legs.
Wings/No wings.
Tails.
Giga Helmets aren't quite the same but are similar.