Wǎng shàng de hēizi zǒng xǐhuān wúyuán wúgù de pīpíng biérén.
Online haters always like to criticize others for no reason.
Tips
register
黑子 in internet slang means a 'hater' or 'detractor', someone who spreads negativity about a person or group online. This usage is colloquial and distinct from the literal meanings (chess piece / sunspot).