Events

Rebirth of the Night includes many events, some of them are outlined below:

Invasions
Invasions increase the mob spawn rates of specific types of mobs, which have higher aggro ranges and can destroy bases. During an invasion, sleeping will be near impossible due to the monsters attacking.

Invasions happen every 9 days, coinciding with seasonal changes.

Moon events
Moon events start happening on night 5, and there is a three day "cooldown" between same events.

Blood Moon
Blood Moons are similar to invasions, but increases mob spawn rates in general instead of having specific types of mobs. The sky and moon turn red, with the moon having a red creeper face on it.

Full Moon
During a Full Moon, enchantment effects such as Lunar Edge will be at its strongest. The first night of a world will always be a Full Moon.

Harvest Moon
Heavily reduces mob spawns (dependent on game progress, in late game doesn't do much) and increases crop growth. Sky and moon gain a purplish tint.

Star Shower
The rate of Fallen Stars occurring is drastically increased. Sky and moon gain a yellowish tint.