may I recommend these youtube channels > youalwayswin at https://www.youtube.com/channel/UCj4I9NfO3xIvl-Ym2Qzib1Q and markiplier at https://www.youtube.com/user/markiplierGAME
fast bullet speed made the enemy's speed up, so the slow made the enemy's slow, and faster relode means more enemy's spawned at a time and, you get the picture by now.
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