1st possibility: lead a rotting corpse away from other spawn - near the dark guardian room in Doom e.g. - and let it attack your discorded cu sidhe. Do this for the full length of a whispering cycle. Rinse and repeat!
2nd possibility: place your discorded cu sidhe west of the Sakkhra village in the Eodon valley so that no opponent could reach it across a river. Lead / lure a dimetrosaur to the other side of the said river ... use another whispering cycle. Rinse and repeat
Don't loose patience!
... picture of a disco training session at the above mentioned place in Eodon
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