Sneaking up the ridge, the players prepare to storm the multilevel Castle Anthrax, a wooden fortress where defenders lurk in its 20,000-square-foot interior and ready their counterattack. The castle is one of seven outdoor playing fields at AG Paintball, which has been featured on WMUR's "New Hampshire Chronicle." Amid forest terrain, participants duck into huts, snipe opponents from behind paint-splattered barrels, and trick the guard sphinxes into unveiling one of the multiple entrances to the Octagon. Updated annually with new fields, the facility hosts both novice and experienced players and matches those of equal experience and skill for games in varying styles of play. After their bouts, guests can restock supplies in the pro shop, commission repairs from the onsite gunsmith, or grill some burgers in the covered patio area, where those 21 and older can also enjoy BYOB privileges once all gear is returned.