Oppenheim: Mechanics

Reap is an ability word that states, "Whenever one or more land cards are put into your graveyard from anywhere, [EFFECT]". This is mostly found on cards. There will be plenty of ways to get lands in your graveyard - discard, self-mill, sacrificing, even pulling Catalyzed cards from exile into your graveyard. Because this is an A+B mechanic and requires a bit of effort, the base bodies that Reap is found on are usually fair and the bonuses are nice and will usually push the game to a close.

Persist makes its return, as do -1/-1 counters. This will mainly show up in colors, but can be dotted throughout the set. It is a minor focus of the set and represents the denizens of Oppenheim struggling to survive.

While not necessarily a mechanic, Wastes and colorless mana () make their return as a minor focus of the set, mostly focused in . This represents both wildlife and beings mutated through radiation, as well as artificial life (robots) as a faction in the set.

In OGW, colorless mana was primarily used as an additional cost for activated abilities, and treated as a special type of mana. In OPN, colorless mana returns in that usage, but has more of a focus on colored denial (denying opponent colors by turning their mana into ). Wastes do not return as a basic land card, but a number of cards may make Waste tokens.

A no-longer-kosher downside mechanic. While these use poison counters, the goal isn't to get your opponent to ten - it's to keep yourself from dying. The flavor is mostly "irradiate yourself to receive a beneficial effect, but too much and you just outright die". While the loss-at-ten isn't listed in the reminder text, it will be on the token itself. I do not anticipate ever reaching ten in a normal game of limited, as removing counters and gaining life will be natural as the game progresses.

These will mostly be attached as either a cost to undercosted cards (mostly removal), or as an optional cost on certain cards. Because you aren't incentivized to draft multiple overdose cards, this mechanic will be spread throughout all colors, though and will have archetypes catered specifically towards managing the effects of overdosing.

Catalyze is a keyword that allows you to use a noncreature card from your hand as a reagent to power up your spells. While you will get the card back once your creature or permanent has left the battlefield, it limits your options temporarily - so don't be committing a nonland card only to discover that you may need it later.

Because it's inherently more low-risk than just "discard a card", a lot of catalyze effects will render the creature harder to deal with on the opponent's side - for example, a catalyze effect in might give the creature hexproof, or a catalyze effect in might make the creature unblockable.

At higher rarities, catalyze effects may be tied to one-off abilities; I haven't decided whether or not this is the best use for it, as it lessens the risk of putting a card in with it in exchange for incentivizing the opponent to use removal on it.