Card sounds may differ from in-game as they get updated.
Endurance - Units with Endurance ready at the start of each players turn, so they can attack and still be ready to block during the enemy turn. Additionally, they are completely immune to enemy stun and exhaust effects.
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.
Nomad - This unit has Flying on your turn and +X/+X on the enemy turn.