Standard is the earliest game mode in Roshan Defense. All other game modes use the same map in Standard as a base, and are mostly played the same way.
Standard Mode has a 5 minutes respawn timer for Jungle Bosses, while Lane Bosses spawn every 10 minutes.
Radiant and Dire creeps will first spawn at 0:20, and then every 30 seconds after that.
Jungle creeps spawn once the game starts, and will respawn 60 seconds after being killed.
On difficulties higher than Herald (Legend/Divine/Immortal), after a random amount of time, the Forpost will start sending waves of creeps towards your base from the south, and then every 2 minutes after that.