If a Therizinosaurus sees you and you don't have a flying tame with you to escape it, you're COOKED! I saw a level 2 Theri kill my level 41 Pteranodon in less than 10 seconds, so yeah, unless you have a flying tame with you, you're somewhere where the Theri can't reach you, or you have it trapped, you're COOKED!

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