Step 1. Find one in a cave unless your on aberration the trap it

Step 2. Tranq it and give it food

Step 3. Make sure it is night unless your on aberration

If it's not night the megalosaurus could be sleep deprived and won't work and will be sharply debuffed so use them at night and again unless your playing on aberration.

I hope this tip was helpful if not I hope it gave you some info on a tame you might want

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