No Error Streak II
250 XP
Make no error for 20 problems.
20/20
Common
Recently completed by
Radek Jančík 11k, 
Ahmet Ayan 10k, 
Furisato Ritsuka 10k, 
Takanashi Touya 7k, 
DLR 7k, 
Jonathan de Koning 8k, 
Mai Trần Hiền 11k,
and 9311 others.
