What is a card's Power cost?

Every unit, spell and gear in Riftbound: the League of Legends trading card game shows its cost in the top left corner, and that cost has two parts. The number in the circle is the Energy cost. The domain symbols stacked under that number are the Power cost, and they tell you how much Power of which domain you must pay to play the card. Many cards have no symbols under their number, and those cards have no Power cost.

Power in this sense says nothing about how strong a card is. A unit's strength is its Might, and Power is a resource that is only ever spent to pay costs.

Where is the Power cost printed on a card?

The Power cost sits right under the Energy cost, in a narrow band of the domain's color with one symbol for each Power the card asks for. Rule 131.3 of the Core Rules defines it as the symbols listed vertically in the cost in the upper left corner, and adds that not every card has them.

Falling Star, a Fury spell from Origins, costs 2 Energy and shows two Fury symbols on a red band, so its Power cost is two Fury Power. Premonition, a Mind spell from Spiritforged, shows three Mind symbols under a 2. Noxus Hopeful has a 4 with nothing under it, so it costs 4 Energy and no Power.

Only the cards of the main deck have a cost, so Legends, runes and battlefields have no Power cost. Symbols inside the text box are not part of the Power cost either: they are the costs of abilities and of extra costs such as Accelerate. A swirling rainbow symbol there stands for one Power of any domain, such as the cost of hiding a card with Hidden.

How do you pay a Power cost?

Each symbol is paid with one Power of its domain. With runes alone, that means recycling one rune of the matching domain for each symbol, which sends the rune to the bottom of your Rune Deck. To play Falling Star, you exhaust two runes of any domain for the Energy and recycle two Fury Runes for the Power, and those may be the two you just exhausted.

A rune exhausted for Energy readies again on your next turn, but a rune recycled for Power leaves the board, so the Power cost is the more expensive part of a card. Recycling needs no ready rune, so the best order is to exhaust runes for the Energy first and then recycle those same runes for the Power, as in how runes pay for cards, where a card of three Energy and two Power is paid for step by step.

How big can a Power cost be?

Most Power costs are small. Across Origins, Spiritforged, Unleashed and Vendetta, the first four main sets, a little more than half of all units, spells and gear have no Power cost, and about nine cards in ten ask for one Power at most. A few cards cost nothing but Power, such as Seal of Rage and the five other Seals of Origins, one for each domain, which cost 0 Energy and one Power each.

Only three cards in those four sets ask for four Power: Commander Ledros and Time Warp from Origins and Elder Dragon from Unleashed. The two parts of a cost do not grow together. Time Warp costs 10 Energy and four Mind Power, while Rhasa the Sunderer costs 10 Energy and a single Chaos Power.

A low Energy cost with a high Power cost is harder to play than it looks. To pay for Premonition with runes alone, you need three Mind Runes on the board, and in a deck that splits its runes between two domains that can take several turns.

How does a Power cost work on cards with two domains or none?

A signature card of two domains prints each Power symbol on a band split between the two colors, and the Core Rules let each of those symbols be paid with Power of either domain. Defiant Dance, the Calm and Chaos signature spell of Irelia, costs 1 Energy and one Power that may be Calm or Chaos. Icathian Rain, the Fury and Mind signature spell of Kai'Sa, costs 7 Energy and three such Power, so a Kai'Sa deck can pay it with any mix of Fury and Mind.

A card with no domain, called a colorless card, fits a deck of any domain, and the Core Rules let a Power symbol on such a card be paid with Power of any domain. Neeko, Blending In, a neutral champion unit from Radiance, the fifth set, with its release on 23 October 2026, costs 6 Energy and one Power on a gray band.

Can a card's Power cost change?

Yes, while the card is being played, although the printed symbols never change. Under rule 356 of the Core Rules, extra costs, increases and discounts are applied before you pay, and no Energy or Power cost can drop below 0. A discount that names a domain symbol lowers the Power cost.

• Discounts. Commander Ledros lets you kill friendly units as an additional cost and costs one Order Power less for each one, so with four units killed he costs 6 Energy and no Power. Kraken Hunter, which costs 3 Energy and two Body Power, costs one Body Power less for each buff you spend as you play it.
• Increases. While Vex, Cheerless is in combat, enemy spells cost 1 Energy and one Power of any domain more.
• Ignoring the Energy cost. A card played ignoring its cost pays neither part, but a card played ignoring only its Energy cost still pays its Power cost. Soulgorger can play a unit from your trash ignoring its Energy cost, so bringing back Rhasa the Sunderer skips its 10 Energy but still asks for its Chaos Power.

Which cards look at a Power cost?

Some cards count the symbols in another card's corner. Hush, a Calm spell from Radiance, counters a spell whose Power cost is two or more. Yordle Explorer, a Body unit, draws you a card whenever you play a card with a Power cost of two or more, and Kraken Hunter, with its two Body Power, is one of those cards.

These cards always read the printed cost, whatever was actually paid, as rule 206 of the Core Rules says. If you spend two buffs on Kraken Hunter and pay no Power for it, Yordle Explorer still draws you a card, because the printed Power cost of Kraken Hunter is two.

What does the Power cost mean when you build a deck?

The Power costs decide which runes a deck needs. A deck plays the two domains of its Legend and brings exactly 12 runes, and a rune recycled for Power gives Power of its own domain only. Count the symbols of each domain across your deck: if most of them are Mind, more of your 12 runes should be Mind Runes. Cards with no Power cost are the easiest to play on time, because any rune can pay for them. Cards with both of your domains or with none can have their Power paid by any of your runes, so their symbols need no counting.

The page of each card on the card list gives its Power cost beside its Energy cost. The split of a deck's 12 runes between the two domains of its Legend decides how often the deck can pay its Power costs, which is the question behind how many runes of each domain a deck should bring.