2 resources and 1 card for 1 action, but 2 cards and 1 card worth 3 actions, so 3 actions for 1 action? Not an impressive card among all those rogue cards providing action. But when export to other factions with Versatile, this ability become priceless. Seekers draw cards so easily, that you can almost consider cards as free. So 2 resources for 1 actions now? If there is any card can get resources as efficient as 1 action (you don't have to count in any cards spent!) for 3 resources, then the combination will become 1 free resource! And then you just use the free resource for more actions! Here is a deck for example.

I think a good use of this card could be with Agnes Baker or on another level with Patrice Hathaway. Combined with Scrying or Scrying(3), you can see 3 cards of your deck, and decide to discard the one you want, especially Treachery Cards. Moreover, correct me if I'm wrong, but Patrice Hathaway can choose the order of the cards in her discarded hand, making Yaotl sensibly more powerful.

The lower cost and ability to reload are pretty great, as are the two skill icons. Combos beautifully with Well Prepared and the Bandolier, ensuring that you don't waste your Shotgun or M1918 BAR rounds on weaker enemies.

Wow! Most tomes are only good for investigators whose names rhyme with Crazy Stalker -- but this might be the rare exception. Assuming I read this right, you peruse the top nine cards of the encounter deck, choose one, and then discard a copy of that card that is currently in play. In other words, if there's a conglomeration of spheres squelching around your map, and you find his twin brother in your 9-card draw, you can discard said conglomeration. Or if someone has a hex or a miserable Frozen in Fear in their threat area, and you find the match, you can discard that too.

This is impressive versatility! Each time you crack your codex, you have a decent chance of discarding literally any non-elite encounter card currently befouling your board -- whether it's an enemy or some treachery, whether it's at a location, in your threat area, or attached to the act or agenda deck.

Let's think about this. We have some cards that let us discard enemies, like the Disc of Itzamna, or Persuasion. We have a couple that can cleanse your threat area -- Logical Reasoning and the very fancy Cheat Death, which you'd only use in an extreme situation. I don't know of any player card that can pick off cards attached to the agenda deck. And here comes this codex that can do all three! All three three times!

Of course, the the codex does come with some chanciness. You may not find the duplicate you were hoping for in your 9-card draw. If there are only a couple encounter cards on the board, you might whiff altogether. The codex gets better and better as the encounter deck dwindles, and as encounter cards start to pile up on the board. It depends on the scenario, but it seems to me that in a three-player game, it doesn't take long for the board to start filling up, and thus for the codex to become reliably useful. If you play it with 3 or 4 encounter cards on the board and 20-25 in the deck, you'll probably get to discard something, even if not your first choice.

So who should take it? In my view, anyone who can... As with all tomes, Daisy can use the action for free -- always nice. Mandy can potentially discard TWO cards from play, which sounds amazing. But really, I think it's great for any investigator. Joe and Roland might prefer to keep their hands free for weapons, but sheesh, the codex can be a pretty dang good weapon in its own right!

If you want to make the Codex a key part of your deck, consider including means of extending its usefulness as well. You might take Astounding Revelation, which will let you add secrets to it, or Knowledge is Power, which will let you use the Codex without burning a secret. For an item this good, it's worth eking as many applications from it as you can!

Ah, bonus experience. People will do crazy things from bonus experience. They might drive themselves insane with Arcane Research, risk catastrophe for everybody from Delve Too Deep or show off their death wish with Charon's Obol. However, how possible is it for someone to slay a giant pile of monsters?

The first and most obvious caveat is that you have to be a monster hunter to hope make this work, and that you must also have access to the Rogue pool. While this is a restriction, it's not one of the heavier ones - a number of rogues can be reasonable monster fighters, and a number of non-rogues have enough access that it's not too hard to add one copy of this.

Second, this means you need to be able to kill 6 HP worth of enemies in one turn. Practically speaking, this generally means that you'll be using it after either finishing off a single large enemy, or a pair of decently chunky enemies. This ends up being a more notable restriction. In smaller games, this is only likely to happen in very specific circumstances. In solo, the only way you'll have 6 health worth of monsters in one turn is if you've had a particularly rough set of turns and failed to finish off a monster along the way, both of which mean you're already in a less than ideal position. In two player, it will require appropriate setup, since a teammate might leave a hunter in place and you can try to arrange for it to approach. It's when you hit three investigators that this becomes merely 'unlikely' - it becomes more plausible that you see multiple monsters. Some guardian tools like First Watch or On the Hunt help to find monsters, while Dynamite Blast can often kill them.

(The primary exception to this is if you're about to hit a scenario where you know an elite monster is coming up, and you want to get into a slugging contest with it. In solo games, elite health might end up on a borderline. However, in two or more player games, elite monsters almost always have enough health that you can try to finish one off.)

Third, in scenarios where you can't finish something off, this is only worth a single symbol when committed. It's a very weak commit option, so you'll only want to include it if you're fairly sure you can use it.

Fourth, it's worth noting the card itself is not fast and ends your turn. For most characters, this means that your final action must be spent to actually play the card. This gives you all of two actions to obtain the required kills, unless you're using Leo De Luca or have some other method of obtaining bonus actions. It also means that you won't be managing two copies unless you manage a second unlikely fight on top of the first unlikely one.

Finally, it's worth noting that the net result of your setup and sacrificed card and action, the reward for this is a single XP for one investigator. All of those conditions end up only helping a single person. This usually means that your entire team needed to coordinate to set this up, and the result is that you spend a single action and card to get a single XP for yourself. Is that much effort going to be any more possible than gaining another XP for the entire group for meeting another victory condition? More often than not, I think the group would rather go for another victory point outright.

With so many different restraining conditions, is this worth it? I think one copy could be playable in a few very specific characters or swapped in with Adaptable when you know there's a good elite target coming up. If a fight occurs in the first mission of the campaign, you might also be able to put it in your initial deck and replace it early. Otherwise, this card is too inconsistent to be worth the card slot. XP is valuable, but I don't think a few bonus XP for one investigator is worth permanently forcing your entire group to play awkwardly and the dead draw it would otherwise represent.

(TL;DR: Probably not worth it. Use Adaptable for elite fights or drop it early. Only leave it in if you're an extremely focused monster fighter in a larger player count game.)