Should you take trauma to defeat non-elite enemies? Probably not. As a Guardian you will very rarely need to take such drastic measures to defeat these kinds of enemies. Every once in a blue moon you'll be caught in a gigantic swarm of enemies, and maybe playing this would help your teammates win a scenario. But that's incredibly rare. The vast majority of this time, this event is not going to help the team win. And remember that many scenarios impose really nasty penalties on defeated investigators, which can make playing this event even more dangerous than it first appears. The physical trauma might not be the full extent of the punishment you take for activating this event.

So what's the point of this card? I see two possible upsides. First, it has two Combat icons, which is generally what Guardians most want to see. I wouldn't run this over Overpower or Unexpected Courage, both of which offer extra perks that are a heck of a lot more useful than I'll see you in hell!'s event, but Guardians who are looking to hit more reliably (probably on higher levels) could run this in addition. I think the Guardian card pool is deep enough that you can probably do better, but still, there are worse things to have in your deck than a cheap +2 bonus to one Combat check.

The second way you could possibly use this card is to avoid mental trauma. Guardians tend to have a lot of health and not very much sanity, so they greatly prefer physical over mental trauma. So, theoretically, you could play this card if you think you're about to die from sanity loss, and instead take the more desirable trauma type (perhaps taking out an enemy or two in the bargain.) This is a cute idea, but I think in practice you would almost always be better off just taking more horror healing cards if you're that worried about mental trauma.

All in all, I don't think this card is all that useful as things currently stand. Its theme is pretty cool, though.

This card is quite effective to "make use of" your ample 9 health, escaping defeat by horror. In Carcosa campaign that the card came with it is actually hard to try to get killed by damage when all hope is lost as you are trying to choose the right kind of trauma.

Also cannot be overlooked is how Mythos Phase draw is reduced once you are gone. If the works are already done then the game could be easier with you (and perhaps some enemies) out of the way, it is suddenly more peaceful. You can have a more deterministic last few turns where you are gunning for extra VP as well as getting out alive at the edge of doom clock.

However, if the remaining investigator can't win on top of your sacrifice, you may doubly suffers new trauma (could be horror still) from the campaign resolution in addition to 1 physical trauma printed on this card. Yikes!

Also sometimes the campaign booklet prepares extra detailed resolution for investigator who were defeated and who weren't, so relying on the remaining player to drag your dead body to finish line requires some scenario knowledge. Card is better on Hard / Expert and with campaign knowledge.

It is also possible that a new player joins mid-campaign with 0 XP (or existing player got asked by the campaign to choose a new investigator) and this card can be quite strong for such an investigator coming in with underpowered gears but with fresh trauma. I'm glad the game has some niche solution for niche situation.

Should you take a trauma to defeat non-elite enemies? If you are a guardian... probably not. But if your investgator is named Calvin Wright, then yes of course!

For him, this card is awsome in so many ways! At first it has 2 Icons, so you can always contribute to a test, if you shouldn't need the event effect. But you are Calvin. You want to be defeated. The more trauma you have (up to 2-3 mental and physikal), the stronger you'll start the next scenario. Later in the campaign you can either still use the 2 icons or upgrade it to "I've had worse…", or something else/similar. In multiplayer this card get's even better. You give your team mates room to breathe and you get your trauma in one go. There are also some enemies with victory points who aren't elite (especially in Dunwich! Look at the Dunwich Artwork and you know one of them...).

Yes, this is a niche card for every other investigator who's name isn't Calvin Wright (also look for Ghastly Revelation).

As others have said this card is not helpful on its own.

So how could it be?

Well, if the "non elite" was removed it certainly would. But then, it would be overpowered.

What if it was fast? Doesn't matter, you're out anyway and getting one extra action out before you blow yourself up probably isn't going to make a difference.

How about cost? It's 0. It can't be any cheaper.

What about if the trauma goes away and you're just defeated? This makes it a little better, but you still probably lose the scenario and those penalties can be worse.

The only thing we are left with then is... what if you aren't defeated? Two ways to do that. Either an upgraded version of this card deals damage to you and everyone at your location to clear then out (wait isn't that just Dynamite Blast), or guardians get an ally that specifically intercepts being defeated (something along the lines of "when you would be defeated, Exile this card. It is defeated instead). This would work, but would also technically screw up encounters as some automatically defeat you when time runs out.

So... there is really no way to make this card useful even with future versions. It's a dead card.

This card actually has a very specific space where a single copy is strong add, one that you're not even likely to cut when upgrading: playing an investigator in multiplayer who uses a playset of Taunt (like Zoey Samaras or possibly other in 3 to 4 player games) on Expert difficulty. Outside of that, the card isn't amazing. It's never as terrible as it seems, but it's probably not as good as building for survivability and consistent damage.

With Makeshift Trap (Improved Timer. + Net.) and some other tricks (Lure/Lure, Bait and Switch, "Get over here!"/"Get over here!", Predator or Prey) you can have your own antimatter singularity for 6 less XP than the boring vanilla Poisonous. + Explosive Device. combo.

Probably still only worth it in Calvin, but this way I think you can truly maximize the output of "I'll see you in hell!".

(I guess it's also viable in Tommy since he can easily take the trauma.)