To catch a slayer monster soul, an ushabti must be in the players inventory when the monster is killed.
Faiza gives you up to 50 Ushabti based on your Slayer level. She will provide 25 Ushabti at level 99 and 50 at level 120, she gives 1 extra per level above 99. If they are claimed before reaching level 99 a new one can be claimed from her after each Slayer level gained.
Can be acquired from Slayer Masters for 20 slayer points each.
To make a Cursed ushabti (empty): use a Cursed amascut sand on an empty Ushabti.