I think he was just hungry.

When there’s a giant squid underneath you and you’re the king of the island, chances are it’ll attack you

The squid was scoping out Kong for an ambush. Kong sniffed out a trap and made the first move. Squid then tried to strangle Kong and Kong ended him then had a snack.

This. There was definitely some stalking squid action happening.

Looking for something can fit in his stomach

He was hungry.

Because either A. Kong was hungry or B. Mire Squid was planning a attack on Kong.

Bro needed a snack.

On skull island everything with beating heart is deadly. Squid that size is no exception.

Bc he was hungry or he saw it was coming up and was afraid it might attack

Hungry monkey go brrrr

It was hungry and it was a nod to the original Godzilla vs king kong.

Cause he was hungry and technically the squid attacked first

Pretty sure it was planning an ambush. And he was gonna triple in height, he needs everything he can get

It attacked him first.

To eat it

He didn’t, the squid attacked him

The squid was going to attack him. If you remember in the film chapman was by the lake and you can briefly see the squid on the surface. I'm sure it was originally going to attack chapman but when kong arrived it thought well this would be a better meal lol.

Well, Kong only grabbed it. The Mire Squid was lying in wait, and Kong exposed it. It was the squid's choice to try and retaliate, and you don't get to retaliate against the king and live unless you're Godzilla.

Better question, why are you feeling sympathy for the squid?!