ShroudShroud is a static ability. “Shroud” means “This permanent or player can’t be the target of spells or abilities.”
Multiple instances of shroud on the same permanent or player are redundant. (CR 702.18) (This creature can't be the target of spells or abilities.)
FlankingFlanking is a triggered ability that triggers during the declare blockers step. (See rule 509, “Declare Blockers Step.”) “Flanking” means “Whenever this creature becomes blocked by a creature without flanking, the blocking creature gets -1/-1 until end of turn.”
If a creature has multiple instances of flanking, each triggers separately. (CR 702.25) (Whenever a creature without
flankingFlanking is a triggered ability that triggers during the declare blockers step. (See rule 509, “Declare Blockers Step.”) “Flanking” means “Whenever this creature becomes blocked by a creature without flanking, the blocking creature gets -1/-1 until end of turn.”
If a creature has multiple instances of flanking, each triggers separately. (CR 702.25) blocks this creature, the blocking creature gets -1/-1 until end of turn.)