The second can end the first before its own effect resolves
The 2024 D&D Basic Rules glossary says you lose Concentration on an effect the moment you start casting another spell that requires Concentration, or activate another effect requiring it. You do not wait to see whether the second “worked” while recording both as active.
DnD Dynamic Sheet supports spell selection, notes and other character data. This guide proposes a manual state check, not automatic cancellation, compatibility detection or Concentration adjudication by the sheet.
Track two fictional effects without inventing official spells
Call our hypothetical spells A and B. Each description requires Concentration. These are not names of included product spells or complete casting rules.
Your initial note says “Concentration: A.” On your turn, you decide to start casting B. At that moment, A loses your Concentration and ends under the general rule. Update the note so it no longer presents A as maintained. Then resolve B’s casting and requirements with the table. Do not record its outcome as confirmed before resolving it.
If you only read B or select it to consult its description, that is not yet starting to cast it in the fiction. Do not change a game state merely because you looked at a card.
Check before confirming the change
- Read whether your current effect requires Concentration and what its description says.
- Check whether the effect you intend to start requires it too. Duration over several turns does not establish that by itself.
- Separate consulting from casting. When the second casting actually begins, resolve loss of the earlier Concentration.
- Record only the state the table has resolved. If B’s outcome is still undecided, mark it pending rather than as a guaranteed second active effect.
Other factors can break Concentration, including damage with the appropriate saving throw. This example concerns switching effects; it does not replace the complete rules or a specific description’s exceptions.
Record a rule without turning a counter into one
DnD Dynamic Sheet’s facts document notes, spells and custom counters. A note you choose can remind you what you are maintaining. Its presence does not show that the program validated a casting or that a custom counter enforces the rule.
D&D Beyond for players and Shard were consulted on 25 October 2026 as other character and session workflows. This example’s rule comes from Concentration in the 2024 Basic Rules glossary, not a comparison of automation.
Review the sheet you plan to use
DnD Dynamic Sheet is available as paid Windows x64 beta 1.6.5 with a one-device licence. Initial activation needs internet; the sheet and local data can then be used offline. Review the presentation and demonstrations before buying. Agree how to distinguish confirmed Concentration from a still-pending decision in your next session.