The Lobster is an arthropod mob that spawns in most ocean varieties. It will not spawn in Warm Oceans. Lobsters are very similar to spiders in health and damage.
Lobsters are hostile during the night time and in low light levels, but become neutral and lay dormant on the sea floor during the day. Like most other aquatic mobs, lobsters will eventually die without water, and will always make an effort to return to a water source if they are beached.
Lobsters are arthropods, and therefore vulnerable to the Bane of Arthropods enchantment.
Though they cannot swim, lobsters can climb an infinite number of blocks so long as they are all underwater.
Lobsters appear during Mob Sieges in hard mode.