1.
Twitch chat usually spams this when a streamer plays dota 2 and is not on par with the perfect skill that the twitch chat has. Since the skill level of the streamer is so much lower than the entire twitch chat, (s)he/it will miss an occasional last hit.

2.
When there's a stream and a commercial for a Counter Strike LAN appears
1.
*Admiral Bulldog misses a last hit*
Twitch Chat: CS LUL

2.
*ESL One Cologne commercial*
Twitch chat: CS LUL
by Sikamixoticelixer January 15, 2017
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The established term to properly write in Twitch chat when someone missed a last hit in Dotes.
by Greblock January 2, 2018
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