a skeleton

• -2570, -389, -41 (35 of 37 spawns here)
• 2299, 343, -46 (2 of 6 spawns here)
• 0, 0, -2008 (seen once) (1 of 60 spawns here)
• 1382, 713, -51 (seen once) (1 of 2 spawns here)
• 1865, -187, -56 (seen once)
• 1685, 1023, -44 (seen once) (1 of 4 spawns here)
• -2092, 172, -54 (seen once) (1 of 2 spawns here)
• 899, 813, -17 (seen once) (1 of 6 spawns here)
• 1588, -682, -46 (seen once) (1 of 3 spawns here)
• 2174, 1023, -33 (seen once) (1 of 2 spawns here)
• -1528, -79, -38 (seen once)
• 1498, 417, -52 (seen once)
• -478, 105, -34 (seen once) (1 of 7 spawns here)
• 1964, 140, -48 (seen once) (1 of 4 spawns here)
• 963, 562, -34 (seen once) (1 of 3 spawns here)
• 1513, 852, -15 (seen once) (1 of 3 spawns here)
• 2158, 802, -21 (seen once) (1 of 3 spawns here)
• 1436, 269, -63 (seen once)
• 2017, 95, -54 (seen once) (1 of 2 spawns here)
• 2025, 135, -47 (seen once) (1 of 5 spawns here)
• 2234, -851, -41 (seen once)
• 2279, -45, -45 (seen once) (1 of 4 spawns here)
• 714, 842, -39 (seen once)
• -1233, -237, -38 (seen once)
• 1246, 523, -44 (seen once)
• 1604, -74, -46 (seen once)
• 1496, 526, -54 (seen once) (1 of 3 spawns here)
• 1378, 1027, -40 (seen once)
• 1028, -316, -53 (seen once)
• 1843, 571, -41 (seen once) (1 of 2 spawns here)

As /loc gives them: Y, X, Z, the most used first; nearby spawns share a spot, and one seen in a single visit may be where the mob had been pulled to.