Neutral Objectives
Objectives across summoners rift will spawn on set timers. The first of these objectives are the powerful elemental 
dragons that give powerful buffs. The first dragon spawns at 5:00, and respawns 5:00 after it is defeated.
The 
Rift Herald spawns at 8:00 for the first Rift Herald, and the second spawns 6 minutes after the first one is defeated.
Once the clock hits 20:00, beware. The powerful 
Baron Nashor spawns. Defeating this objective will typically require your entire teams cooperation. Defeating it awards you with a temporary buff that empowers your ally minions.
Finally, the 
Elder Dragon will spawn 5 minutes after the last elemental dragon is defeated. Slaying the Elder Dragon will eempower you and surviving allys to execute enemy champions below 20% health.
The first team to manage to slay all four dragons, is awarded with a powerful dragon soul that will permanently buff you and your allies for the entirety of the game. Only one dragon soul is awarded per game.