In complex with rde-11, required in the endogenous and exogenous siRNA pathway for biogenesis and accumulation of secondary small interfering RNA (siRNA) intermediates, such as 22G-siRNAs derived from ergo-1 targets. Interacts with rde-11 (via RING-type zinc finger domain) (PubMed:22508728, PubMed:22542102). Interacts with ergo-1 (PubMed:22542102). Insensitive to RNAi-mediated gene silencing. Belongs to the maelstrom family.