Necro Calculator

Necropotence exiles cards face down through life-paid activations. Delayed triggers put them into hand at the beginning of your next end step; these are not draws. Activations made during that end step wait for your next one. Necrodominance instead takes a life payment and draws when its beginning-of-end-step trigger resolves. Its five-card hand limit applies at cleanup, and its graveyard replacement affects rituals and sacrifices. Necrologia costs {3}{B}{B}, is cast only during your end step, and takes life as an additional casting cost.

Dark Ritual spends {B} and adds {B}{B}{B}. Cabal Ritual spends {1}{B} and adds three black, or five with threshold. Culling the Weak spends {B} and sacrifices a creature as an additional cost to add four black. Sacrifice spends {B}, sacrifices a creature and adds black equal to its mana value. A zero-mana-value creature supplies nothing through Sacrifice. These instants need starting mana and preserve their actual output colors. Black mana can pay Borne’s generic portion, but cannot replace its blue requirement.

Rain of Filth costs {B} and lets your current lands sacrifice themselves for {B} until end of turn. There is no tap cost, so tapped lands qualify. Enter other existing sacrificial lands, excluding battlefield Emergence Zone. The same land cannot fund Rain and Crop Rotation. Newly accessed lands do not count. Creature inputs describe existing permanents by mana value and token status. Each sacrifice consumes one permanent. Count its ordinary mana only once in starting mana.

Desperate Ritual and Pyretic Ritual each spend {1}{R} and produce {R}{R}{R}. Seething Song spends {2}{R} and produces five red. Splice is outside this model. They can pay generic costs or Final Fortune’s red requirement, but cannot manufacture blue. Manamorphose instead filters two mana into two chosen colors and draws a card; it is outside this calculated resource set.

Borne Upon a Wind costs {1}{U}, grants spell casting this turn as though spells had flash, and must draw a card safely. High Fae Trickster costs {3}{U}, has flash and grants permission for all spells while present. Valley Floodcaller costs {2}{U} and grants only noncreature spell permission. Shimmer Myr costs {3} and grants artifact permission. Liberator, Urza's Battlethopter costs {3} and grants colorless and artifact permission. Restricted access does not make Thassa’s Oracle castable.

An existing Lotus Petal supplies one chosen color. An existing Lion’s Eye Diamond can supply three of one color before Necro cards arrive, discarding the old hand. Activating it afterward discards the new hand. An existing Skirge Familiar discards cards for black, consuming those cards. Newly accessed rocks need suitable flash permission first. Include existing mana once in Mana available; discard-based conversions and post-flash artifact sequences are not automatically calculated.

Crop Rotation needs a sacrificial land, {G}, and Emergence Zone still in the library. Then pay {1}, tap and sacrifice Zone for flash permission. Zone cannot also tap for mana. Accessing Zone removes this searchable route. A battlefield Zone can activate directly; one in hand cannot ordinarily be played during the end step. Without an exact land count, Crop’s prerequisite remains a labeled assumption.

Cast Snapback using a separate blue hand card and a legal creature target. Retain priority and spend {U} on An Offer You Can't Refuse targeting Snapback. Offer creates two Treasures after spending that initial mana. The pitch cannot be Snapback or Offer used here, or the reserved action. Pitching another continuation consumes its copy. Simian Spirit Guide supplies red and Elvish Spirit Guide green; neither supplies initial blue. Resources are spent once per sequence.

For direct targets, Find uses the hypergeometric probability 1 − C(N−K, X) / C(N, X), where N is library size, K is target copies and X is cards accessed. With four direct targets among 90 cards, accessing 20 finds at least one about 64.1% of the time. Crop and Zone need a dependent calculation: one of each among 10 cards, accessing 3 gives 7/30, approximately 23.33%. Usable checks sequences and resource consumption. Overlapping categories are counted once overall. Large resource populations use a seeded simulation, labeled with uncertainty in Details.

Total-only mana estimates suitable colors, spent once. Set colors to verify payments. Cabal checks threshold on resolution, before entering the graveyard. Earlier instants and sacrificed nontoken permanents can increase that count under Necropotence; Necrodominance exiles them instead. A sacrificed commander returned to the command zone does not remain as threshold fuel. Mana to keep after the action checks a generic reserve, not a combo’s colors or protection. Mark known cards outside the library to keep estimates possible.

Mana empties as each step or phase ends. End-step mana therefore cannot be carried into cleanup. Discard triggers from Necropotence can open a cleanup priority window, but until-end-of-turn effects have already ended when that priority arrives. Borne or Rain cast earlier no longer applies there. Necrodominance’s graveyard replacement alone creates no such discard trigger. This calculator evaluates the end-step window before cleanup, not a cleanup escape loop. Demonic Consultation and Tainted Pact measure castable hand-access actions, not guaranteed retrieval; Final Fortune includes a delayed loss.

Drake Sasser’s Shimmer Zur primer explains the ritual, flash enabler and artifact sequence through firsthand testing. It dates from 2023, so its decklist is historical. Evan Pierce’s RogSi guide discusses choosing between a refill and an immediate attempt. Rules here follow linked Oracle records and Wizards’ rules, effective September 25, 2026. Opposing interaction, stax, cost modifiers, post-flash rocks and complete win combos are outside the calculation. Compare general draw odds or explore Commander Tools.

Use the life slider to compare Find and Usable with your available mana. More cards do not guarantee a usable action. Enter current life in Details to leave at least 1 life, and budget separately for life-paid protection.

No. It measures a supported action with configured resources and any mana reserve. Restricted flash access may not cast your win condition. Opposing interaction and full combo execution are outside the model.

Crop Rotation must reach your hand while Emergence Zone stays in the library. With one of each among 10 cards, accessing 3 gives 7/30, approximately 23.33%, before mana and battlefield checks. Accessing every card leaves no Zone to search for.

No. Borne grants spell-casting permission for the turn. It does not change ordinary land-play timing or allow abilities restricted to sorcery timing. Its mandatory extra draw also means an empty remaining library makes that continuation unsafe.

No. Simian Spirit Guide supplies red and Elvish Spirit Guide green. The Snapback and Offer sequence needs initial blue mana before its Treasures exist. Generated mana retains its actual color even when starting colors are estimated.

Enter mana spendable in this end step after paying for the selected source. For Necrologia, its casting cost is already paid. Include existing sources once. Main-phase floating mana does not automatically carry into the end step.

Choose or import deck opens saved decks and imports. This browser restores your last selected account deck, or your latest updated deck. This does not publish it or change its visibility. Anonymous visitors can paste a decklist or import a supported public deck. Only Main Deck cards are analyzed.

Usually they need a suitable flash permission first. The calculator uses supported instants and Spirit Guides to pay for access. It does not assume a drawn Lotus Petal or mana rock is already on the battlefield.

No. Cabal Ritual needs seven cards in your graveyard when it resolves. Necropotence puts its accessed cards into hand, not the graveyard. Necrodominance prevents new graveyard cards while its replacement effect applies.

It requires unspent mana immediately after the action, using assistance beforehand from accessed or known cards. Later spells and Borne’s extra card are not modeled. This generic reserve does not verify a combo or its colored costs.