- Internal NPC ID: 1022
While Lepus is alive, the music Boss 1 will play.
Lepus hops towards the player for most of the battle, occasionally pausing to launch a Lepus Egg and then leaping at the player.
Lepus lays two types of Lepus Eggs: small ones that hatch Diseaster Bunnies, and bigger ones that hatch another weaker Lepus. These eggs can be damaged and destroyed by the player before hatching. A maximum of five Lepus can be spawned from the large eggs laid by the original Lepus, and after there are five, no more large eggs will be laid. Each Lepus will drop items, but only the last one will drop the Egg Cannon or Boots of Ostara. If Lepus is defeated while an unhatched large egg is still present, it will spawn around 3–6 Diseaster Bunnies instead of a new Lepus.
- Internal NPC ID: 1023
- Defeating Lepus will fulfill the requirement for the Dryad NPC to spawn.
- Lepus rarely drops Souls of Might, one of the only two Hardmode crafting ingredients obtainable pre-Hardmode, the other being the Crystal Shard, dropped by Arch Demons.
- Lepus has the second most health out of all the pre-Hardmode bosses, more than the health of the Wall of Flesh and less than Turkor the Ungrateful.
- Lepus will always spawn towards the center of the map. If the player is to the right of the center, Lepus will spawn on the left and vice versa.
- The large number of Diseaster Bunnies spawned by Lepus, combined with the fact that he drops his summon item when he dies, makes Lepus a very viable method for getting Biome Key Molds.
- Lepus can be a renewable source of coins once the player gets late Pre-Hardmode gear, since he will always drop his Suspicious Looking Egg.
- Lepus can be trapped easily, since it cannot fit through small gaps, but its smaller Diseaster Bunnies can still reach the player.
- Trapping Lepus in a deep enough pit and firing downward can also be effective.
- Lepus can easily overwhelm beginners by spawning more, weaker versions of himself, so destroying the Lepus Eggs should be a priority.
- Like most seasonal content, Lepus can be fought by changing the device's date to a day in April, when Easter is set to occur. Not all devices will allow the date to be changed, however.
- It is possible to farm coins by creating a pit with traps (preferably Lihzahrd) and jumping in with the traps disabled. The player can then grab the coins and grapple out (with no fear due to all the dropped hearts).
- Lepus can be attacked while the player takes low to no damage by making a tall staircase mostly because Lepus has such a large and odd AI causing him to slide down stairs at the end of a leap, however Diseaster Bunnies can use stairs correctly.
- When in Hardmode, summoning Lepus in different biomes can be used to farm their rare Biome Key Molds, but the player must be careful to let small eggs hatch and not to kill the Lepus itself.
- Lepus has an unused animation: instead of standing before making an egg, it would close its eyes and fold its ears, then open its eyes and mouth, and lift its ears up.
- The word "Lepus" means "hare" in Latin, and is used today as the name of the genus that hares and jackrabbits belong to. Rabbits, known alternatively as "bunnies" and associated with Easter, are not actually members of Lepus.
- Lepus and Turkor the Ungrateful are the only bosses who do not drop trophies.
- Lepus used to drop Greater Healing Potions even before Hardmode was added until it was patched in 1.2. This made it by far the easiest way to obtain large amounts of Greater Healing Potions.
- Maps on the version do not show boss icons. This makes Lepus one of the three bosses that do not have a boss icon, the other two being Ocram, and Turkor the Ungrateful.
- Mobile 22.214.171.124: Removed.
- Mobile 1.2.6508:
- Mobile 1.1.91: Introduced "officially".
- Mobile 1.1.8: Introduced "secretly".
- 3DS-Release: Introduced with changes from Mobile 1.2.6508.