Vashta Nerada

Shadow is an evasion ability.

A creature with shadow can’t be blocked by creatures without shadow, and a creature without shadow can’t be blocked by creatures with shadow. (See rule 509, “Declare Blockers Step.”)

Multiple instances of shadow on the same creature are redundant.

Indestructible is a static ability.

A permanent with indestructible can’t be destroyed. Such permanents aren’t destroyed by lethal damage, and they ignore the state-based action that checks for lethal damage (see rule 704.5g).

Multiple instances of indestructible on the same permanent are redundant.