The strongest. Ever. There is no use arguing with her. She's absolutely the strongest and the fastest and the smartest. Everything she says is the word of God. Nothing anyone says will ever be true if she says it's not true.
Cirno completely trumps every non-fairy being in Touhou and some more.
Powers and Stats
Tier: -9 (-1/(0.9^∞))
Origin: Touhou Project
Classification: Badass Ice Fairy, Heroine, Strongest Fairy, The Strongest, Nineball, Ice God
Powers and Abilities: Cryokinesis, Immortality, Flight, Transformation, Courage, Main Caracter Title, Plot Manipulation, Spatial Manipulation, Time Manipulation and Immunity to Time Stop (Memorized Sakuya's power somehow when she was older), Omnipotence Manipulation, Ability to be automatically stronger than anything any character either existing or not existing either can or can't potentially reach.
Attack Potency: City Block - at her base form, Endless - Has frozen and shattered the ninth dimension at her strongest base form, Bypasses any durability - Has booped TOAA for calling her stupid.
Speed: Infinite Speed
Lifting Strength: Can easily lift whatever she freezes. Even something that weights an infinite amount.
Striking Strength: Always nine times stronger than you
Durability: Weak - at her base form - Survive her own cryokinesis
Stamina: 99x better than normal humans
Range: 99x infinity
Standard Equipment: Watermelon Sword, A calculator to counter her math issues, a Badass beard
Intelligence: Calculated the value of pi in the ninth dimension
Weaknesses: Math, called idiot all the time