4c4414c8__Your_Protos_Are_Belong_To_Us___2
[0] Yo-Yos [2] 
Yo-Yo's move just like their name suggests. They move forward and then quickly move back. The trick to killing Yo-Yos is to get behind them and shoot before they snap back. Unlike other enemies, Yo-Yo's won't move all the way across the screen.
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