Halfbreed races are a common staple of fantasy.

Half-Orc +3STR, -1MIND
Half-Elf +1MIND, +1 comm
Mul (Half-Dwarf) +1STR, +1 phys
Quarterling (Half-Halfling) +1DEX, +1 sub

Half-Fiend +3MIND, -1STR or -1DEX

Half-Stone Elemental +3STR, -1DEX
Half-Air Elemental +3MIND, -1STR
Half-Water Elemental +3DEX, -1MIND
Half-Fire Elemental +3MIND, -1DEX