Frill-Necked Lizard
If you rewatch the scene tobi is in then this makes senses this is what he was doing this is what frill necked lizards do.
It mainly forages for food in the morning and late afternoon and spends the rest of its time on tree trunks and limbs. Its long slim front limbs and strong hind legs enable it to stretch and move easily between branches. It scans the ground for prey from the trees then rapidly descends and runs on two legs along the ground, before dropping onto four legs to seize its prey.
If threatened, it will sit back on its hind legs and open its mouth to expand its frill. It then hisses and may jump towards the predator. If that has no effect, it will turn quickly and run away on two legs to climb the nearest tree and hide behind the trunk or a branch.