Start from a flat line. At each step, one random empty site touching the cluster fills.
Tap to raise a spike and watch it get absorbed. The same ?seed= always gives the same run.
LITEden growth; its interface is in the Kardar–Parisi–Zhang class (β = 1/3). Every 30 steps the filled-site ledger must match a fresh count, or the page throws.
AMBERA single run on a finite strip only approximates the exponent.