S: (v) club (gather into a club-like mass) "club hair"
S: (v) hive (gather into a hive) "The beekeeper hived the swarm"
S: (v) salvage, scavenge (collect discarded material) "She scavenged the garbage cans for food"
S: (v) muster, rally, summon, come up, muster up (gather or bring together) "muster the courage to do something"; "she rallied her intellect"; "Summon all your courage"
S: (v) round up (seek out and bring together) "round up some loyal followers"