My Favourite and Easiest way to get a Basilosauros:

Get icthy. Pump health and speed. Get prime meat or kibble or whatever you have (preferably kibble, prime meat or mutton) and put it in last slot. Feed to Basilosauros, hop onto icthy really quick, then bait all the mantas as far away from the Basilosauros as possible. Most will not go back for Basilosauros. Rinse and repeat with new mantas he picks up along the way, boom easy Basilosauros.

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