The native Klein Gordon page uses normalized speed c equal to one. Its telemetry computes angular frequency as the square root of wave number squared plus rest mass squared. Compare the native mass slider at zero and one, while wave number remains two. At zero mass, frequency is two, and both phase speed and group speed are exactly one. At mass one, frequency is square root five. The phase speed becomes about one point one one eight zero three four, while group speed is about zero point eight nine four four two seven. Blue bars encode phase speed and pink bars encode group speed, using three hundred twenty pixels per normalized speed unit. These are exact held source formula comparisons, not measurements of a full wave packet trajectory. A phase speed above the normalized speed of light does not by itself imply that information or signals propagate above it. Now examine one actual interior cell in the reset barrier preset. At grid coordinate twenty five, fifty, the field is one and the previous stored field is the Float thirty two value of cosine zero point two. Its four reset neighbors determine the displayed discrete Laplacian. The source advances the field using twice the current value minus the previous value, plus time step squared times acceleration. The native time step is zero point one five. Compare an unpainted center with the native barrier brush, which assigns potential three point five at the center. Keep all current and previous field values, neighbors and mass one identical for this local comparison. The barrier subtracts three point five from acceleration. Its next field value consequently falls by approximately zero point zero seven eight seven five, with the actual Float thirty two storage rounding included in the displayed results. Each held bar uses five hundred pixels per field amplitude. This teaches the causal local update rule, not an asserted complete scattering trajectory. The selected interior cell receives no boundary damping. The mass brush changes a different term. It assigns local mass four, while the reset center has local mass one. In the source acceleration, mass is squared, so its coefficient increases from one to sixteen. For the same reset center, previous value and neighboring fields, with potential zero, this subtracts fifteen more from acceleration. At the native time step zero point one five, the next stored field falls by about zero point three three seven five, again with Float thirty two rounding. Blue and pink bars encode the exact held local results at five hundred pixels per amplitude unit. The native eraser clears potential and restores local mass to the current mass parameter. Painting and erasing are actual canvas controls, while these figures compare their exact local coefficient effects. The source energy display squares the discrete Laplacian and omits some physical terms. Treat it as its own numerical proxy, not calibrated Hamiltonian energy or a proof of conservation. The phase color mode is also a derivative based approximation, not an independently established complex quantum phase.