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LINER nuclei comma the long-lived comma low-accretion-rate states of supermassive black holes comma are critical for understanding the AGN phenomenon in the context of galaxy evolution. Observations have established the presence of black-hole related activity in most LINERs. But comma we have also learned that the line emission on virgul1d_comma (virgul100 pc) scales comma used for LINER classification with ground-based data comma is not balanced by the radiative energy output of the nucleus alone. Another comma V1.0 power source provides most of the power on these scales. The leading candidate is centrally-driven outflows of gas that carry at least as much power as the radiative luminosity of the AGN and produce optical emission lines through shock heating. Past HST case studies of four LINERs have spatially resolved the line-emitting regions comma suggested a transition from photoionization on scales of tens of pc to shock excitation on larger scales comma and allowed estimates of the kinetic power. Thus comma LINERs may be signposts of feedback from the AGN onto the host galaxy. As such comma they help us understand more distant comma important objects. But a larger comma truly representative sample comma spanning a wider range of LINER AGN properties comma is needed to test and generalize those results. We propose optical spectroscopy comma spatially resolving virgul0.1 arcsec scales comma for a diverse and representative sample of 15 LINERs. We have designed an economical observing program by exploiting spectra available in the archive for a large fraction of the targets. We will carry out the first comprehensive mapping and exploration of the excitation of LINER gas using multi-dimensional line-ratio diagrams on scales of virgul10 pc.