If you have a stego already, a good strategy would be to ride your previously tamed stego with heavy plate equipped. You hit the stego with heavy plate to start, slowing it while aggroing so it stays in range, then switch to hardened plate (the slowing debuff should give you plenty of time to do so) then, equip a crossbow with tranq arrows (personal preference, but ultimately it’s up to you) the aggro on the stego will keep it close enough to be able to steadily headshot the stego, while you being in your stego will prevent it from retaliating and lowering its health. You will probably have to periodically hit the stego with heavy plate equipped to keep the slowing debuff active, but other than that you should be fine

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