diff --git a/overviewer_core/src/block_class.c b/overviewer_core/src/block_class.c
index 7fc7187..d9e9b0b 100644
--- a/overviewer_core/src/block_class.c
+++ b/overviewer_core/src/block_class.c
@@ -31,6 +31,28 @@ bool block_class_is_subset(
     size_t block_class_len) {
     size_t i = 0;
 
+#if defined(__AVX512F__) && defined(__AVX512BW__)
+    for (; i / 32 < block_class_len / 32; i += 32) {
+        const __m512i block_class_vec = _mm512_loadu_si512(
+            (__m512i*)&block_class[i]);
+        const __m512i block_vec = _mm512_set1_epi16(block);
+        const __mmask32 block_cmp = _mm512_cmpeq_epi16_mask(block_vec, block_class_vec);
+        if (block_cmp) {
+            return true;
+        }
+    }
+#endif
+#if defined(__AVX2__)
+    for (; i / 16 < block_class_len / 16; i += 16) {
+        const __m256i block_class_vec = _mm256_loadu_si256(
+            (__m256i*)&block_class[i]);
+        const __m256i block_vec = _mm256_set1_epi16(block);
+        const __m256i block_cmp = _mm256_cmpeq_epi16(block_vec, block_class_vec);
+        if (_mm256_movemask_epi8(block_cmp)) {
+            return true;
+        }
+    }
+#endif
 #ifdef __SSE2__
     for (; i / 8 < block_class_len / 8; i += 8) {
         const __m128i block_class_vec = _mm_loadu_si128(
diff --git a/overviewer_core/src/overviewer.h b/overviewer_core/src/overviewer.h
index 0296647..a8b9c88 100644
--- a/overviewer_core/src/overviewer.h
+++ b/overviewer_core/src/overviewer.h
@@ -31,7 +31,7 @@
 
 // increment this value if you've made a change to the c extension
 // and want to force users to rebuild
-#define OVERVIEWER_EXTENSION_VERSION 109
+#define OVERVIEWER_EXTENSION_VERSION 110
 
 #include <stdbool.h>
 #include <stdint.h>