Every champion has four unique abilities mapped to Q, W, E, and R keys. The R ability (ultimate) is typically the most powerful and has the longest cooldown. Abilities scale with champion level and items, becoming more potent as the game progresses.
Summoner spells provide additional strategic options. Flash (instant short-range teleportation) is nearly universal due to its versatility for both escaping danger and engaging enemies. Other popular choices include Ignite (damage over time), Heal (health restoration), Teleport (long-range map movement), and Smite (required for jungle monsters).