League of Legends' Free-to-Play model allows gamers, paying or not, to enjoy all of the core gaming experience.
So every element that actually makes a difference in the gameplay can be acquired for free (champions & runes). There are more than 60 champions in the game and they are locked for you when you create an account; you buy a champion for a given price with in-game money (IP - Influence Points) earned by playing the game, or you spend Riot Points. Runes give you a small boost in-game, and can only be bought with IP.
Riot Points (RP - acquired spending real money) are used for:
- Boosting Summoner Experience/IP gain per game (summoner level cap is 30)
- Buying champions
- Skins (cosmetics)
- Changing your Summoner Name (more cosmetic, basically)
- Others (Bundles, Extra Rune Pages, etc.)
In short, not spending money means you will take longer to unlock all features (which are not required for having fun with the game), you will not have skins, and your Summoner Name is fixed.
A major difference between 5s and 3s is how much lane control you need to win the game. To summarize: for 3s you want high dps champions with a lesser focus on team value, and in 5s you want high lane control champions with great team value.
In 5s you value champions that can hold their own lane well, because teammates will leave their lane open for minutes while they travel to help you. In 3s you value champions that can help other lanes and contribute lots to ganking, because traveling lane to lane takes very little time.
Champions like Heimerdinger and Soraka do well in 5s because they both have great lane control. Heimerdinger's turrets and passive heal allows him to push a lane very well and stay in good shape, meaning he doesn't need to leave the lane for a heal and spend a minute running back out. Soraka can heal herself and replenish mana, so she almost never needs to leave a lane.
However, in 3s they are less handy because they are squishy and susceptible to being ganked. They also provide little value when it comes to ganking in other lanes because they are not damage-per-second champions. To contrast Heimerdinger and Soraka, Tryndamere is a champion who shines in 3s. He can quickly travel from one lane to another by spinning over walls, and his dps makes ganks easy.
Another thing to note is that you require team composition in 5s, as any one champion can be focused down by 5 others at a time without a team backing them up. In 3s it's less of a problem because champions last longer in team fights as less damage is going around. Tryndamere in 5s can be crowd controlled by 5 other champions and he provides no aid to his teammates. However, in 3s he can solo two champions and likely win.
Best Answer
League of Legends is a MOBA, Multiplayer Online Battle Arena. You battle with your team to fight the enemy team to destroy towers guarding the enemy base, and then destroy said base. An average match of League of Legends lasts for about 20-50 minutes, though some matches may exceed this.
In the new playstyle, Dominion, your team tries to capture a majority of the 5 capture points on the map while defending the points you own. The team who can keep a majority of the points longest wins. These matches usually don't last more than 25 minutes.
There are (currently) 95 champions that any person can play, after unlocking them with real money or in-game points, each with several abilities and all with their own stats. By working with your team you can choose a character to support others, kill the enemy team, distract the enemy team or keep the enemy from acting.