This has to be about their positioning. Paracers should be tamed at the green obelisk since going in a swamp is risky and titanboas or sarcos or kappas can attack you anytime. Isolate them from their pack and knock them out. Feed them with kibbles and when they are tamed immediately equip them with at least only a normal saddle and ride them back to your base to make the platform saddle later. It might be complicated but that’s how I tamed mine.

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