A network can require every identity to emit a verifiable-delay-function heartbeat before its actions count: each agent must produce a VDF proof chained from its own vertex in the identity graph, a computation that consumes a fixed wall-clock interval on commodity hardware and cannot be parallelized across cores. Like the yarrow stalk that grows one shoot at a time, identity must ripen sequentially, so a Sybil farmer spawning a thousand sock-puppets buys only a thousand sequential waits. The protocol pulse keeps ticking; the attacker's clock simply stalls.