Correct spelling, explanation: the word threatened is a past simple/past participle form of the regular verb threaten. It consists of two parts: the basis and the common -ed suffix. The aforementioned verb – threaten – comes from the noun threat. It’s important to remember that many English verbs end with -en. You can’t omit this part of the construction. Therefore, the only correct form is threatened, not threated.

Definition of threatened:
verb (past simple, past participle), to warn of something unpleasant or unwanted
My husband threatened to sue the company he works in for mobbing.
The attacker threatened them with a gun.

Collocations with threatened:
Some most commonly used collocations include threaten to do something.
The boss threatened to sack him.
Connor’s wife threatened to divorce him.

Incorrect spelling, explanation: threated is an incorrect version of the word threatened. It lacks the important part which is the -en suffix, which is used to create verbs. Without it, the construction doesn’t make any sense. Be careful not to make that mistake. Threatened is a past simple/past participle form of the verb threaten. You can’t just add a verb suffix to the noun.