Level 1
Poison Provisions: +6% casualties for all units
Poison Wells: +6% casualties for all garrison units
+1 cunning
Level 2
Poison Provisions: +12% casualties for all units
Poison Wells: +12% casualties for all garrison units
+2 cunning
Level 3
Poison Provisions: +18% casualties for all units
Poison Wells: +18% casualties for all garrison units
+3 cunning