diff --git a/source/games/blood/src/fx.cpp b/source/games/blood/src/fx.cpp
index 9ee8ec4fe..074b71f03 100644
--- a/source/games/blood/src/fx.cpp
+++ b/source/games/blood/src/fx.cpp
@@ -32,18 +32,18 @@ CFX gFX;
 
 struct FXDATA {
     CALLBACK_ID funcID; // callback
-    char at1; // detail
-    short at2; // seq
-    short Kills; // flags
-    int at6; // gravity
-    int ata; // air drag
+    uint8_t detail; // detail
+    short seq; // seq
+    short flags; // flags
+    int gravity; // gravity
+    int drag; // air drag
     int ate;
-    short at12; // picnum
-    unsigned char at14; // xrepeat
-    unsigned char at15; // yrepeat
-    short at16; // cstat
-    signed char at18; // shade
-    char at19; // pal
+    short picnum; // picnum
+    uint8_t xrepeat; // xrepeat
+    uint8_t yrepeat; // yrepeat
+    short cstat; // cstat
+    int8_t shade; // shade
+    uint8_t pal; // pal
 };
 
 FXDATA gFXData[] = {
@@ -166,23 +166,23 @@ spritetype * CFX::fxSpawn(FX_ID nFx, int nSector, int x, int y, int z, unsigned
     }
     spritetype *pSprite = actSpawnSprite(nSector, x, y, z, 1, 0);
     pSprite->type = nFx;
-    pSprite->picnum = pFX->at12;
-    pSprite->cstat |= pFX->at16;
-    pSprite->shade = pFX->at18;
-    pSprite->pal = pFX->at19;
-    sprite[pSprite->index].detail = pFX->at1;
-    if (pFX->at14 > 0)
-        pSprite->xrepeat = pFX->at14;
-    if (pFX->at15 > 0)
-        pSprite->yrepeat = pFX->at15;
-    if ((pFX->Kills & 1) && Chance(0x8000))
+    pSprite->picnum = pFX->picnum;
+    pSprite->cstat |= pFX->cstat;
+    pSprite->shade = pFX->shade;
+    pSprite->pal = pFX->pal;
+    sprite[pSprite->index].detail = pFX->detail;
+    if (pFX->xrepeat > 0)
+        pSprite->xrepeat = pFX->xrepeat;
+    if (pFX->yrepeat > 0)
+        pSprite->yrepeat = pFX->yrepeat;
+    if ((pFX->flags & 1) && Chance(0x8000))
         pSprite->cstat |= 4;
-    if ((pFX->Kills & 2) && Chance(0x8000))
+    if ((pFX->flags & 2) && Chance(0x8000))
         pSprite->cstat |= 8;
-    if (pFX->at2)
+    if (pFX->seq)
     {
         int nXSprite = dbInsertXSprite(pSprite->index);
-        seqSpawn(pFX->at2, 3, nXSprite, -1);
+        seqSpawn(pFX->seq, 3, nXSprite, -1);
     }
     if (a6 == 0)
         a6 = pFX->ate;
@@ -203,7 +203,7 @@ void CFX::fxProcess(void)
         assert(nSector >= 0 && nSector < kMaxSectors);
         assert(pSprite->type < kFXMax);
         FXDATA *pFXData = &gFXData[pSprite->type];
-        actAirDrag(pSprite, pFXData->ata);
+        actAirDrag(pSprite, pFXData->drag);
         if (xvel[nSprite])
             pSprite->x += xvel[nSprite]>>12;
         if (yvel[nSprite])
@@ -257,7 +257,7 @@ void CFX::fxProcess(void)
                 continue;
             }
         }
-        zvel[nSprite] += pFXData->at6;
+        zvel[nSprite] += pFXData->gravity;
     }
 }
 
@@ -349,9 +349,9 @@ void fxPrecache()
 {
     for (int i = 0; i < kFXMax; i++)
     {
-        tilePrecacheTile(gFXData[i].at12, 0, 0);
-        if (gFXData[i].at2)
-            seqPrecacheId(gFXData[i].at2, 0);
+        tilePrecacheTile(gFXData[i].picnum, 0, 0);
+        if (gFXData[i].seq)
+            seqPrecacheId(gFXData[i].seq, 0);
     }
 }