What Star Battery Actually Does
Every other character in Slay the Spire 2 spends what it earns on the same turn. Energy resets, Strength applies to the attack you play right now, orbs evoke and clear. The item:regent runs on a different clock. Stars do not reset between turns. A Star generated on turn one sits in the bank waiting for turn three, when the right payoff card lands in your hand. Star Battery is built around that bank: cheap generators on early turns, big spends when the bank is full.
The Forge layer compounds in parallel. A Forge effect played on any turn permanently raises the damage of item:sovereign-blade for the rest of combat. The blade itself is a 2 energy token with Retain that the first Forge effect each fight drops into your hand. Every Forge after that pumps the same blade higher. By Act 3 a Forge-fed deck can swing a single 2 energy attack for 40+ damage on a Retained card you draw automatically.
The full Regent plan fuses these two tracks. Star Battery and Forge Blade share the same card pool, the same Skill-heavy reward picks, and the same payoff turn. Treat them as one build.
How Stars and Forge Work
Stars persist between turns inside a single combat. The first turn you spend a card to gain 2 Stars, those Stars sit in the bank on turn two if you do not spend them. The wiki confirms this. What the wiki does not flatly state is whether Stars carry between combats. Combat-start grants from item:divine-right (3 Stars) and item:divine-destiny (6 Stars) almost certainly mean that Stars reset per fight, but no source spells it out. Treat the bank as resetting at the start of every encounter until in-game testing proves otherwise. The cap is also undocumented; v0.102.0 may run uncapped.
Star-cost cards consume Stars on play. You need to afford both the energy and the Star cost. A card listed as 0 energy, 2 Stars still requires 2 Stars in the bank or it will not play. Cards that cost X Stars dump the entire bank when played.
Forge works one way. The first Forge effect played each combat adds Sovereign Blade to your hand. The blade is a Token, not a deck card; it cannot be drafted. It costs 2 energy, has Retain so it sticks in hand turn over turn, and starts at 10 base damage. Every Forge after the first adds its full Forge value to every copy of Sovereign Blade in play, including any copies already exhausted that combat. If the blade is exhausted or transformed, the next Forge spawns a fresh blade at base damage; previous progress does not transfer.
When to Pivot Into Star Battery
The build wants specific pieces. Without them, you have a starter deck with one Star generator and one Star spender, which is not enough to drive a full run. These rewards tell you the run is pointing at Star Battery.
Genesis offered in any Act 1 reward. Mobalytics calls Genesis the strongest Star generator in the game; it reads as a Power that grants 2 Stars at the start of every turn for 2 energy. Exact effect text has not been verified on the source wiki, but if the description holds, Genesis doubles your generation rate from a single power play. Take it the moment it appears.
Glow or Gather Light in opening Act 1 rewards. Both are 1 energy commons that generate a Star. item:glow draws and pre-loads a draw for next turn. Gather Light gives 8 Block on top of the Star. Either one is the foundational generator the deck needs. Two of them in Act 1 puts the engine on schedule.
item:falling-star+ from a campfire upgrade. Upgraded Falling Star deals 12 damage with Weak and Vulnerable for 0 energy and 2 Stars. Very few cards in the game turn 0 energy into 12 damage with two debuffs attached. Upgrading the starter at the first campfire is one of the highest-value uses of the Smith.
An early Forge-tagged uncommon, especially Bulwark. Bulwark gives 13 Block and Forges 10 for 2 energy. That is a defensive card that also pushes Sovereign Blade past 20 base damage on its first appearance. Picking it up tells you the Forge half of the plan is online.
Touch of Orobas in Act 2. This event is the single biggest power spike for the Regent. Taking it converts Divine Right into Divine Destiny: 6 Stars at combat start instead of 3. That extra reserve is enough to play Falling Star+ on turn one with no setup, every fight, for the rest of the run.
If none of these signals show up in Act 1, stay flexible. The starter deck handles Act 1 fine without commitment.
Core Cards
Falling Star (Basic, Attack). 0 energy, 2 Stars, 8 damage with 1 Weak and 1 Vulnerable. Upgraded: 12 damage. The starter payoff, not a generator. It cashes in 2 Stars for a free attack with two of the best debuffs in the game stapled on. With Divine Destiny in Act 2, you have the Stars to play it on turn one of every fight.
item:venerate (Basic, Skill). 1 energy, gain 2 Stars; upgraded gain 3. The only Basic Star generator in the starting deck. Upgrade it early.
Glow (Common, Skill). 1 energy, gain 1 Star, draw 1 card, next turn draw 1. Upgraded jumps to 2 Stars. The card you want in hand on turn one because it generates a Star, replaces itself, and seeds next turn's draw. Glow is doing three jobs at once.
Gather Light (Common, Skill). 1 energy, 8 Block plus 1 Star; upgraded 11 Block. Block matters because the curve eats turn one and two on generation. Gather Light covers most chip damage from a single Act 1 enemy intent while still feeding the bank.
Sovereign Blade (Token, Attack). 2 energy, Retain, 10 base damage. Dropped into your hand by the first Forge effect each fight. Once in hand, Retain holds it across turns, and every Forge after the first raises its damage. Nothing to draft; the card shows up the moment your deck plays its first Forge card.
Refine Blade (Common, Skill). 1 energy, Forge 9, next turn gain 1 energy. Upgraded Forge 13. The 1-energy refund pays the card back in tempo. Forge a 9-damage boost, get the energy back next turn, swing a 19-damage Sovereign Blade for 2 energy net.
Spoils of Battle (Common, Skill). 1 energy, draw 2, Forge 5. Pure tempo. Refills the hand and adds 5 damage to every Sovereign Blade in play.
Wrought in War (Common, Attack). 1 energy, 7 damage, Forge 7. The only confirmed Forge attack. Real damage on cast while feeding Forge for the Act 2 boss.
Bulwark (Uncommon, Skill). 2 energy, 13 Block, Forge 10. The flagship Forge enabler. 13 Block absorbs most Act 2 enemy turns whole, and Forge 10 puts Sovereign Blade past the threshold where it kills basic enemies in one swing.
Other key payoffs are referenced by name in community sources but their numbers have not been verified against the source wiki. Comet is described by Mobalytics as the strongest Star payoff in the game. Gamma Blast reads as a stronger Falling Star. Reflect blocks while dealing damage. The Smith is listed in the Forge keyword page with a Forge value of 30 to 40, the largest single Forge documented. Big Bang, Conqueror, Summon Forth, and Beat into Shape are also listed as Forge cards with no further numbers. Hidden Cache and Royal Gamble are listed as Star generators. Take any of these on sight; the costs and damage will be visible in-game when they appear.
For a card-by-card ranking that complements this build, see the Regent card tier list.
Relic Priorities
Divine Right (Starter). 3 Stars at the start of each combat. Already in your possession. Enough to play Falling Star on turn one if you draw it, with one Star left in the bank.
Divine Destiny (Starter upgrade). 6 Stars at the start of each combat. Acquired by accepting Touch of Orobas in Act 2. Doubles the opening reserve. Two Falling Stars on turn one becomes a real possibility, and a single 6-Star X-cost payoff lands without any setup at all. The most important decision the Regent makes in a run.
Lunar Pastry (Rare, Regent-exclusive). Gain 1 Star at the end of every turn. The only Regent-exclusive relic with confirmed effect text on the source wiki. A free Star per turn stacks linearly with the bank and turns long fights into a guaranteed payoff turn every three to four rounds. Take it on sight.
item:ice-cream (Universal, Rare). Carries unspent energy into the next turn. Falling Star at 0 energy and 2 Stars naturally leaves energy on the table; Ice Cream banks that energy for the next turn's Sovereign Blade swing. Pairs with Refine Blade's energy refund to enable 4-energy turns on demand.
item:paper-phrog (Universal, Uncommon). Vulnerable becomes a 75% damage bonus instead of 50%. Falling Star applies 1 Vulnerable on every cast. Every payoff swing into a Vulnerable target hits 25 percentage points harder. Pairs with Sovereign Blade's single-target damage profile better than almost any other relic in the game.
The other Regent-exclusive relics on the source wiki are Fencing Manual (Common), Galactic Dust (Uncommon), Regalite (Uncommon), Mini Regent (Rare), Orange Dough (Rare), Vitruvian Minion (Shop), and Crown of Stars at an unconfirmed rarity. Effect text for these has not been documented at the time of writing. Pick them up when offered, but plan around the four relics named above for build identity.
Act-by-Act Gameplay
Act 1: Bank Stars, Find Generators
Your starter deck has Divine Right's 3 opening Stars, Venerate for one more generator, Falling Star for one payoff, and a base of 4 Strikes and 4 Defends. Act 1 is about bringing the engine up from one generator to three or four.
Take every Glow and Gather Light offered. Take Wrought in War if it appears. If a Forge-tagged Skill is offered, evaluate the deck: if you already have Wrought in War or a multi-hit option, Forge Blade is alive and Bulwark or Refine Blade is a strong pickup. Skip extra Strikes; v0.102.0 Inflation at A6+ makes removal expensive, and every padding card you add now sticks for the rest of the run.
The Act 1 boss does not require the full engine. Falling Star with Vulnerable applied, plus a Bulwark block turn if you have one, is enough.
Act 2: Touch of Orobas and the Engine Locks In
Touch of Orobas is the decision that defines the rest of the run. Take it. Divine Destiny's 6 opening Stars means turn one of every fight starts with a Falling Star option, and most fights end before the boss gets a second action.
Act 2 rewards are where Bulwark, Refine Blade, and Spoils of Battle should fill out the deck. Aim for two Forge enablers by the end of the act so Sovereign Blade reliably drops into your hand on turn one of any combat that lasts longer than a couple of turns. If a rare reward offers Genesis, Comet, or The Smith, take it without thinking.
Act 2 elites at A6+ with Inflation are the hardest part of the run for the Regent. The starter deck does not have enough block to absorb a sustained elite turn unless Bulwark is online, and the slow ramp leaves you exposed if you whiff on early Star generation. Plan to enter Act 2 elites with at least 13 Block available per turn and Falling Star upgraded.
Act 3: Cash the Bank
A fully assembled deck in Act 3 has two parallel win conditions on the same turn. Sovereign Blade comes in pre-Forged for 30 to 50 damage on a 2-energy Retain card. The Star bank refills every fight thanks to Divine Destiny and Lunar Pastry, and Falling Star+ closes the gap with 12 damage and two debuffs for free.
Build: 37383cf4f84cA typical Act 3 boss turn: turn one opens with 6 Stars from Divine Destiny and a hand that includes Glow and Falling Star. Play Glow, gain 2 Stars, draw 1, now sitting at 8 Stars. Play Falling Star for 12 damage with Vulnerable applied, dropping to 6 Stars. The boss loses 30 to 40 percent of its HP before it has acted twice.
Counters
Burst Act 1 elites. The slow ramp gets punished by enemies that close fights in three turns. The starter deck has one payoff card and one generator; if the elite kills you on turn three, the bank never paid out. Plan elite fights around stockpiling on turn one, defending hard on turn two, and dumping Falling Star on turn three.
Multi-enemy rooms. Sovereign Blade is single-target. Falling Star is single-target. The Regent's primary damage tools all hit one enemy. In a three-enemy room with low-HP attackers, the deck has to lean on Wrought in War and basic Strikes while Sovereign Blade takes out the highest-priority threat. AoE potions are worth holding for these rooms.
A10 Double Boss. Forge does not carry between combats. Stars almost certainly reset between combats. Sovereign Blade is a token, not a deck card, so it leaves your hand at the end of the first fight. The second boss starts with a fresh Sovereign Blade at base 10 damage, an empty Star bank, and whatever Divine Destiny's 6 Stars provide on the first turn. Build for this by ensuring reliable Forge generation in the early turns and at least one Falling Star copy per fight.
What We Do Not Yet Know
The Regent is the newest character in the game, and several details rely on community sources that have not been fully confirmed against the source wiki. The honest gaps:
The Star bank's per-combat reset rule is implied by combat-start grants on Divine Right and Divine Destiny but is never explicitly written down. The bank's maximum cap is undocumented; v0.102.0 may run uncapped. Star costs and damage values for Comet, Gamma Blast, Reflect, and the larger Star payoffs are referenced by name in community guides but have not been published in any consulted source. Genesis's exact effect text follows the same pattern. Six of the seven Regent-exclusive relics have no documented effect text on the source wiki at the time of writing, with only Lunar Pastry's effect captured in passing on the Stars page.
When you encounter these cards and relics in a real run, the in-game text is the source of truth. Verify against what you see, not against what this guide infers.