>>30218407Basically in Lol, both sides emit waves of minions. These minions come out in groups, at a constant rate, and meet in the middle cancelling each other out. However if you kill a wave of your enemy's minions, the minions will now collide and cancel out further towards your opponent's side. Thus you can "push a lane" by pushing your minion chain up towards your opponent's side. The big obstacles are the towers, which do a lot of single-target damage. For a player to take one down, ideally he needs minions supporting him.
The players are tremendously more powerful than the minions, and get even more powerful as they level up. To get experience you need to "last hit" a minion, so you finish it off. Last-hitting consistently is an important skill in LoL. The lanes have the most experience, but in between the lanes is a jungle area filled with some mobs and experience as well. Although junglers are going to be a bit under-leveled compared to laners. Sometimes large beasts spawn in the jungle that require an entire team effort to kill, in exchange for significant buffs to your team. The junglers can sneak around behind an enemy lane and surprise them, thus securing kills for your team. Ganking your enemy like this is key to winning. It's also the reason people are very cautious about over-extending too deep into enemy territory, even when they apparently have the advantage.
All of the items, and powerups, nobody really knows. Basically each character has a specific build they are going for, that they already have planned out. So that part is not really important to the game. What's important is getting player-kills, leveling up. Once your team has more levels, you can seriously bully the other team and start pushing into their base. The other team will try to claw their way back with ambushes and pick-offs.
Unfortunately league games tend to snowball, not many comeback mechanics for the losing side to have hope.