Flying

Vanishing 3 (This creature enters with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)

When Chronozoa dies, if it had no time counters on it, create two tokens that are copies of it.

Hexproof (This creature can't be the target of spells or abilities your opponents control.)

Silhana Ledgewalker can't be blocked except by creatures with flying.