like the proverbial Guizhou donkey which has exhausted its tricks—at one’s wit’s end;at the end of one’s tether
黔驴技穷qián lǘ jì qiónɡ
黔：贵州省的简称；穷：尽。黔地的毛驴本领用尽了。比喻有限的本领已经用完了。the proverbial donkey in ancient Gui Zhou has exhausted its tricks, at one’s wit’s end, have shot one’s bolt, have no other tricks left to play