How to stop someone from dying when they would have been killed (with a certain weapon/tag)

[sly seal]

i have a weapon that should run commands on someone when they are kill. However, given that they die, I can't do anything. How do i stop them from dying, or at least appear to do so? I can give more info if necessary.

[fluid basin]

Does the weapon actually need them to not die, or do you just need to run commands as them when they die?

Cause you can do the latter

[stone raft]

You could make the weapon have the totem of undying component and then just give the item back.

[sly seal]

I have misworded this, sorry! 😅 I meant to say that i need the person killed by the item not to die. There will be some special effects, then they will be put in spectator. Does anyone know if this is possible? I was thinking about setting immediate respawn to true really quickly then teleporting them to their death location.

[fluid basin]

In that case then yes as HeDeAn said, you can give the item a death_protection component so that it behaves like a totem of undying, and just detect when that gets used via an advancement to run a function that does whatever you need

[sly seal]

i

am the smartest man alive

i meant to say the person killed by the item

sorry again man

[stone raft]

You can do that with a custom enchantment. more specifically with the post_attack effect.
make the item deal 0 damage, and in the effect, target the hit player and run a function. That function compares the players health and how much damage it would deal. If the if the the damage would kill the player run a different function instead if it doesn't, just run a damage command.

This method has some slight drawbacks, like it can't easily increase the damage with sharpness or other enchantments unless you specifically program that in or the damage/health comparison can't easily calculate the targets armor protection and overall damage reduction.

[frank onyx]

Can't you detect the origin of death through advancement and target @s in the reward function ?

[fluid basin]

Yes, but they don't want or need to have the player die

[sly seal]

well doesn't that select the attacker and not the victim

because if not i may use that

[sly seal]

yeah no that is how it is

wait

how do you select the attacker in entity_killed_player?

[frank onyx]

{
    "criteria": {
        "a": {
            "trigger": "minecraft:entity_killed_player",
            "conditions": {
                "player": {},
                "entity": {},
                "killing_blow": {}
            }
        }
    }
}```

Attacker is under entity

[sly seal]

ah thank you!

i assume killing_blow is the weapon used?