Side Decking
Riftbound's 8-card side deck is small but mighty. Knowing which 8 cards to bring and which to swap in for each matchup is what separates auto-piloting your 40 from adapting to the room.
The Big Idea
Your side deck is 8 cards you only see between games. Once a match begins, you're locked into your 40 — but between games you can swap any of those 40 with cards from your side deck, one for one. The answers that were dead in game 1 are live in game 2, and the cards that were core to your plan in game 1 might be the first cuts. Knowing how to side correctly is what separates a player who beats their good matchups from a player who beats every matchup.
What an 8-card side deck is for
The cards in your main deck are tuned for an "average" matchup — the best mix you've found across the field. Your 8 side-deck cards are tuned for specific matchups where the average mix isn't enough.
Common side-deck categories:
- Hate cards — narrow answers to a specific archetype (e.g. tempo disruption vs aggro, removal density vs combo).
- Tech cards — niche tools that are strong in 2–3 matchups, dead in the rest.
- Counters — cards that if you see will completely counter an opponents gameplan.
With only 8 slots, every card has to earn its spot in multiple matchups. There's no room for hyper-specific cards that only swap in once a tournament — those are luxuries other formats can afford, not yours.
How to side deck
Most players will look up champion specific guides for a "Remove this add this" style of sideboard. Most times that is the easiest way to get confidence on your choices.
If you want to get better as a player that isn't always the best approach.
Sideboard guides only go so far to capture a meta at the time of the guide. You need to evolve past that and make decisions in the moment that is best for your current game.
The instinct is to bring in everything that "looks good" against the matchup. That's wrong. Every card you bring in means a card going out — and the card going out is rarely irrelevant.
For the rest of this section I'm going to step aside and share a framework from another player — JeyTCG (@JeyTCG). The words inside the box below are his, not mine. I've kept his voice intact so the credit is clear and the framework reads the way he teaches it.
1. Think in categories, not individual cards
The biggest mistake people make is thinking card by card.
I think in categories. For example:
- Charm and Rebuke both compete for removal slots.
- Defy and Not So Fast both compete for counterspell slots.
When I sideboard, I ask:
- Do I want to increase the total number of cards in this category?
- Or do I want to diversify my answers within the same category?
That distinction is critical.
Example: Charm vs Rebuke. If I add Rebuke, I ask: am I increasing total removal density, or am I simply replacing Charm because Rebuke is better in this matchup? If I only want to adjust my removal profile, I swap within the category. If I want more removal overall, I cut from a different category entirely.
Example: Defy vs Not So Fast. In some matchups, one is clearly stronger. If I add more Defy, I usually cut copies of Not So Fast to keep the overall counterspell density stable. I rarely want to flood my deck with too many reactive spells — the ratio matters.
2. Identify what actually matters in the matchup
Before I side, I ask these questions:
- What part of their deck is difficult for me to deal with?
- Which of my cards are underperforming in this matchup?
Your ins and outs should answer one of those problems. If they don't, you're just moving cardboard around.
— Framework by JeyTCG | Sideboard Notes
Answer 3 questions
- What's coming in? Usually 1–4 of your 8 side-deck cards. Bringing in all 8 is rare and usually means you've miscounted what's actually live.
- What's going out? The same number of cards from your main deck. Cuts are usually situational answers, slow plans, or duplicates you don't need a full set of.
- Does the new 40 still have a plan? A side-deck plan that breaks your curve, removes your win-cons, or eliminates your engines is worse than not siding at all.
Common mistakes
- Trying to cover every matchup. With 8 slots, you can realistically prepare for 3–4 archetypes — not 8. Pick the matchups you expect, accept that some bad ones will stay bad.
- Cutting your win-con. If you cut the cards that actually win the game, you've handed the matchup to your opponent's grindy game plan.
- Filling slots with "good cards" instead of swap targets. A card that's strong in a vacuum but never an obvious cut from your main deck is wasting a side-deck slot.
- Not having a plan for game 3. Your opponent will side against your side. The plan you brought in for game 2 might not survive their game-3 swaps.