Try it like this.
local combat1 = createCombatObject()
setCombatParam(combat1, COMBAT_PARAM_EFFECT, CONST_ME_FIREWORK_YELLOW)
setCombatParam(combat1, COMBAT_PARAM_TYPE, COMBAT_NONE )
setCombatParam(combat1, COMBAT_PARAM_DISTANCEEFFECT, CONST_ANI_BOLT)
local combat2 = createCombatObject()...