Slay the Spire 2 rest or upgrade: choose safely

Slay the Spire 2 rest or upgrade: Rest when the next unavoidable fight needs more health than your current kit can reasonably protect; Smith when you can survive and the upgrade improves an important turn. Hizzle uses the coming encounter, not one fixed HP percentage, as the deciding question.

Know what the default Rest buys

The checked rest-site reference gives the ordinary heal as 30% of maximum HP. The wiki’s indexed rule rounds down. With 80 maximum HP, that is 24 HP before modifiers; a character at 35 would reach 59 if no other effect intervenes.

That is arithmetic from the stated default, not a guarantee for every relic, event, custom run or mod. Check the actual offered action and heal. Single source for the full currently read rest-site explanation: Untapped’s guide, with a limited wiki excerpt cross-check.

Inspect the actual upgrade

An upgrade can change cost, damage, duration or another important effect. Open the preview before choosing it. A better card you cannot afford to draw and play before dying is not a usable answer to the next fight.

For example, Main Bash’s published upgrade increases damage from eight to ten and Vulnerable from two to three. Whether that prevents more damage than resting depends on the target, your other attacks and the coming draw. The upgrade is not automatically correct just because Bash is in your deck.

Do not confuse Smith with Regent’s Forge

At a normal rest site, Smith upgrades a card. Regent’s Forge is a separate combat mechanic involving the Sovereign Blade. Read the option actually shown rather than treating the names as interchangeable.

Relics can add or alter rest-site actions. UNSURE: every modifier and exact high-Ascension breakpoint; this draft does not promise one universal “always upgrade” rule.

Related: Slay the Spire 2 beginner guide: first run, Slay the Spire 2 Ironclad build: early plan, Slay the Spire 2 achievements: current status, Slay the Spire 2 patch notes: Main versus Beta, Slay the Spire 2 deck size: how many cards?, Slay the Spire 2 Regent guide: Stars and Forge, Slay the Spire 2 Necrobinder guide: Osty and Doom.