= Solution
\b[The <stationary-indexed club principle> $\clubsuit_S$ asserts a sequence $\langle A_\delta:\delta\in S\cap\operatorname{Lim}(\omega_1)\rangle$ with each $A_\delta\subset\delta$ cofinal of order type $\omega$, such that for every uncountable $X\subseteq\omega_1$ some $\delta\in S$ satisfies $A_\delta\subseteq X$.] It predicts a cofinal ladder contained in the target, rather than predicting the entire initial segment of the target as diamond does. For a stationary $S$ with successor members, only its stationary limit-ordinal part is relevant; countable <limit ordinals> have <cofinality> $\omega$. This is the restricted version of the <club principle>.
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