OptiFine
Website: https://optifine.netAdds support for HD textures and often increases performance.
For Minecraft 1.5.2
OptiFine 1.5.2 HD U D5
OptiFine_1.5.2_HD_U_D5.zip
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OptiFine 1.5.2 HD U D2
OptiFine_1.5.2_HD_U_D2.zip
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For Minecraft 1.2.5
OptiFine 1.2.5 HD C6
OptiFine_1.2.5_HD_C6.zip
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For Minecraft b1.7.3
OptiFine 1.7.3 HD G
OptiFine_1_7_3_HD_G.zip
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For Minecraft b1.6.6
OptiFog_Optimine_1.6.6
OptiFog_Optimine_1.6.6.zip
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OptiFog_Optimine_1.6.6_A
OptiFog_Optimine_1.6.6_A.zip
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OptiFog_Optimine_1.6.6_B
OptiFog_Optimine_1.6.6_B.zip
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OptiFog_Optimine_1.6.6_C
OptiFog_Optimine_1.6.6_C.zip
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OptiFog_Optimine_1.6.6_C.zip
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