Parallel drainage pattern. A parallel drainage system is a pattern of rivers caused by steep slopes with some relief. Because of the steep slopes, the streams are swift and straight, with very few tributaries, and all flow in the same direction.
1 In Creative, the player can use spawn eggs to spawn most mobs. 2  When mobs are spawned this way, all normal spawning requirements, such as light level and block type, are ignored. 3  Any entity can be spawned using the /summon command.
Mob Spawner. Mob Spawners, also known as Monster Spawners, are Blocks with a transparent, black, cage-like, lattice structure found in various locations. Inside the Block are flames that don't give off any light and a miniature spinning version of the Mob it spawns which will slowly increase in speed until the next group of Mobs is spawned.