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Must I Pay the Whole Cost If I Cannot Do Everything?
Pay a cost in full to get its linked effect; impossible effect instructions are handled differently.
RiftPal explanation · Answer first
The short answer
A cost must be paid in full to get the effect linked to it. You cannot pay part of a required cost and claim a smaller version of the effect.
The instruction to do as much as possible applies to carrying out effects. It does not let you skip unpaid costs. If the effect itself includes an impossible instruction, carry out the possible parts, while respecting any conditions that depend on earlier actions.
RiftPal explanation
How it works
Card reference
Brazen Buccaneer
A cost appears before an activated ability's colon, as an Additional CostA payment added to a card or ability's base cost. Mandatory additional costs must be paid; optional ones become part of the payment when you choose them. A chosen optional additional cost reduced to 0 still counts as paid.View in Glossary , or in wording such as “do X to do Y.” You must be able to pay X to get Y.
Unit
Brazen Buccaneer
As you play me, you may discard 1 as an additional cost. If you do, reduce my cost by [Energy 2].
An optional payment lets you pay the required amount or decline it, not pay less. Declining means you do not get its linked effect. If you paid but a later part of the effect is impossible, you do not get a refund.
Pay costs inside a spell or activated ability's effect when it resolves. A triggered ability works differently if its effect begins with a cost, including after an opening “you may”: pay that cost while finalizing it on the ChainAn off-board zone that holds cards and abilities during the process of playing them. Cards and abilities on it are public information.View in Glossary . Costs later in its effect are paid during resolution. If you decline its cost during finalization, the ability is removed; it is not countered.
An applicable replacement effect can substitute another event for a payment action. The cost still counts as paid. This does not let you skip the action yourself.
Read separate “pay ... If you do” instructions carefully. If the payment is a game action rather than a cost, the later instruction needs that action to actually happen. Replacing it does not satisfy the “if you do” check.
In practice
Example
Example 1 - Discarding as a cost
An ability requires you to discard 2 cards to draw 3. You have only 1 card in hand. You cannot pay the discard cost, so you do not draw 3; discarding just 1 does not buy part of the effect.
Example 2 - Discarding as an effect
A resolving effect simply instructs you to discard 2, with no linked benefit being purchased by that discard. With only 1 card in hand, discard that card and carry on with any remaining possible instructions.