The second major battle of the war resulted from the deliberate attack by a small Union army under BG Nathaniel Lyon upon a combined secessionist encampment of the Missouri State Guard under Sterling Price and a Confederate Army under BG Benjamin McCullough. Since early July, the Federal forces had backed the Missouri State Guard of the secessionist (but not yet seceded) state government of Missouri into the southwest corner of the state, where a small Confederate force reinforced it. Facing the imminent mustering out of his three-month regiments, Lyon audaciously chose to move his 5000 men against the 11,500 secessionists. Even more audaciously, Lyon divided his force and sent a column under BG Franz Sigel to attack from the rear of the secessionist camp. The secessionists had overwhelming numerical advantages, but were even more ill-equipped and inexperienced than the Federals whose primary advantage was surprise.

This scenario starts with the 5 am attack of the main body of Lyon’s force on the camp of the Missouri State Guard. Little of the Missouri State Guard had the time to respond in sufficient force to the relentless and disciplined Unionist drive. Resistance stiffened only after Lyon reached very strong defensive positions on commanding ground later called "Bloody Hill." At the other end of the encampment, Sigel’s appearance had called a similar panic, but faced the better equipped Confederates who rallied more quickly.

Victory is determined by a combination of 2 of the 3 following objectives:

• Control of the junction hex;

• Control of the Bloody Hill (hex 10-28);

• Destruction or Neutralization of the opposing army (see below).

Control of the junction hex and Bloody Hill is determined by physical occupation. Neutralization of the larger secessionist forces (CSA) requires inflicting at least three times the losses of the Federal. Destruction of the Union forces requires inflicting 50% casualties (the historic result was about 25%). The determination of the scenario winner is done at the end of Turn 6.

By 9 am, the secessionists had rallied sufficiently to drive off Sigel’s column of 1200 and focused their attention focused on Lyon’s 3600 men at Bloody Hill. Although Lyon’s men stubbornly held against a series of uncoordinated attacks, Lyon was killed around 10:30, and Major Samuel Sturgis took command. Towards noon, Sturgis took advantage of a lull in the attacks to withdraw his men, nearly out of ammunition, to Springfield, which they also later abandoned when pressed.

A secessionist victory that could not be sustained, the battle delayed the Federal control of the area until Spring 1862, but it also established a pattern that denied either side an absolute and secure control of most of Missouri, leaving it bitterly divided and contested through most of the war. Also, the Confederate victory, combined with the earlier victory at Manassas, reinforced the Southern "conventional wisdom" of martial superiority and reinforced the views Jefferson Davis in a defensive national strategy that would plague him once the quick victory he expected did not materialize.

There is no strategic movement allowed by any unit in this scenario. No unit is allowed to assume the breastworks "bw" formation. All CSA forces on the east side of Wilson’s Creek (the creek is represented by the pond squares) may not move on T1 though they may fire if able (this represents the surprise Lyon achieved by his dawn attack).