Card sounds may differ from in-game as they get updated.
Entomb - The ability of a unit with Entomb will activate when it dies. This combines well with effects that sacrifice units as a cost.
Flying - Flying units can only be blocked by other flying units, but can block ground units normally. They can also be directly attacked by Killer units and Relic Weapons.
Bond - When played, you may exhaust another unit of the same type to reduce this card’s cost by the exhausted unit’s strength.