try this one, and change effects/attacks etc.
local combat = createCombatObject()
setCombatParam(combat, COMBAT_PARAM_TYPE, COMBAT_DEATHDAMAGE)
setCombatParam(combat, COMBAT_PARAM_EFFECT, CONST_ME_BATS)
setCombatParam(combat, COMBAT_PARAM_DISTANCEEFFECT, CONST_ANI_SUDDENDEATH)...