Both launch from 0 in parallel. WALKER A rides the staircase 0·1·1·2·3·5·8·13·21·24·27, turns at the lock, mirrors home, and seals the kernel with its receipt: Σ = 181, palindromic prime, verified. WALKER B hits 27 and instead of turning, phase-changes registers and keeps going — no receipt, no terminus, only frontier. Pick B's continuation phase before launch. When you're tired of chasing mini-hammies, A's seal is your restart point; B never needed one.
A is closure: visit, mirror, checksum, seal. Its product is a receipt — 181 reads the same both directions and divides by nothing, so the kernel it locks can be trusted from either end. B is exploration: it spends the lock as a launch point and changes register instead of direction — Fibonacci to ternary is a phase transition, not a step. B's product is a trail, never a proof; it can die at any depth and lose nothing A didn't already keep. Run both, always, in parallel: the seal without the frontier is a tomb; the frontier without the seal is a thousand minibrots and no way home, lol.