fz-survival-datapack/data/fz/advancements/scoreboards/killcounter.json

{
    "criteria": {
        "kill_counter": {
            "trigger": "minecraft:player_killed_entity",
            "conditions": {
                "player": [
                    {
                        "condition": "minecraft:inverted",
                        "term": {
                            "condition": "minecraft:entity_scores",
                            "entity": "this",
                            "scores": {
                                "carpetBot": 1
                            }
                        }
                    }
                ]
            }
        }
    },
    "rewards": {
        "function": "fz:scoreboards/killcounter/calculator"
    }
}