The short scenario I decided to try out first in my examination of Prelude to Disaster is Scenario 6: Fridericus in the South, which is a 3-turn scenario of the German operations south of Kharkov. The aim of the Germans is to cut off the southern Soviet pincer threatening to envelope Kharkov. The objectives are the two towns marked with the red star markers. The Germans have 2 mobile divisions, 60 Motorized and 14 Panzer, and will receive a third, 16 Panzer, on the second turn. The scenario starts on game turn 3.
Starting at Turn 3, Soviets are player 1, but play starts at the beginning of player 2's HQ Operations phase. All HQs, Soviet included, start supplied in Defensive mode. The Soviets have no supply points to boost their level to Attack, but the Germans have 4 ready points at the operational HQs, plus more in the rear. However, since the phase for assuming supply modes is already past, the Germans will have to live with Defensive Mode and the subsequent loss of operational effectiveness (-2 effectiveness, -2 movement).
German HQs move up in the HQ Operations phase, to be in position for their advancing divisions. Since in the next phase the German player will conduct operations 1 HQ at a time, he has to figure out which combat units will be under the command of each HQ and that the HQ has the command points, range and supply level to support them before the combat units even begin to move. The Germans have 3 HQs (3 Panzer Korps, 44 Jaeger Korps, 52 Korps) and the subordinate units are easily assigned: the 2 mobile divisions (60 Mot, 14 Pz) to the 3 Panzer, the 3 Jaeger divisions (97, 100, 101) to the 44 Jaeger and the 3 infantry divisions (68, 257, 389) to 52. Each Korps is in Defensive mode, so they have -2 engagement points to spend commanding their units. Luckily, the leader von Mackensen is with 3 Panzer, so he adds an extra engagement point to that HQ.
52 Korps has 4 engagements points to spend, and spends 2 to manoeuvre 2 divisions forward. It can afford an assault (2 EP) with 1 stack, but declines. 44 Jaeger Korps has 6 EPs and manoeuvres 2 divisions forward, leaving 4 EPs to assault from 2 hexes. The odds are determined by rolling efficiency checks (d6 vs. efficiency rating) for attacking and defending units; 1 German division makes the roll and gets to use its primary combat factor, as does the defending Soviet division, but the other German fails and uses its secondary combat factor, giving 14:5 or 2:1. Die roll modifiers are +2 for German artillery support from assaulting units participating or stacked with them, so the 44 Jaeger Korps HQ and the 101 Jaeger each contribute 1. Also, von Kleist has moved into the 44 HQ, so he adds a +1 bonus as well. For good measure, the Luftwaffe makes an appearance, adding a further +4. The final roll is 13, giving the result D1R1, pushing the Soviet 349 Division back with a step loss and making it check morale. The morale check is successful and the division retreats without disrupting. The Germans advance for free into the vacated hex, but since leg units cannot exploit (and the HQ hasn't the EPs to pay for it) that ends the combat. 44 Jaeger reduces its supply level from Defensive mode to Depleted because it assaulted with more than 1 division.
3 Panzer Korps has 6 EPs and uses 2 of them to move 14 Panzer division and 60 Motorized division to attack for 4 EPs. 1st Panzer Army heavy artillery is in range to lend support. The Soviets make their efficiency check with a roll of 1, but the Germans fail with a roll of 5 (they are -2 efficiency due to being in Defensive Mode), so the odds are 14:6 or 2:1 again. This time, the Germans have better DRMs: +2 from the heavy artillery, +1 for von Mackensen and their armour bonuses (reduced by failing their efficiency check) add only +1. Also, since each mobile division has all its units stacked together, both get a +1 for divisional integrity. Add in the air support with +4. Final tally with +10 is 13: yielding another D1R1 result, requiring a morale check by the Soviet division. It fails the check, so it loses a step, retreats and disrupts.
The 2nd turn of the scenario begins with Reinforcements phase, in which the Soviets get a weak infantry division and a decent tank brigade. The Germans get the 16 Panzer division, which will attach to the only HQ eligible to command mobile divisions: 3 Panzer.
Next is the Irregular Operations phase and the Soviets roll to activate their partisan. No luck! Then comes the Communications Phase for each player in which command and supply statuses of units and HQs is determined. Every unit must determine its command status in relation to its operational HQ (6 movement points away, except German mobile, which can be 8 MP away). All Germans are within range, but the Soviets have 2 infantry divisions on the east flank which are marked Out of Command Control, so they must spend the turn moving toward their HQ.
Next is supply mode segment, when HQs consume supply points and assume supply modes, so the Germans put all their operational HQs in defensive supply, since they don't have enough for attack supply. This costs 52 Korps 2 SP and 44 Jaeger Korps 1 SP. There is a special German rule called Limited Offensive Mode which allows the Germans to put individual divisions in attack supply at a cost of 2 supply points per mobile division and 1 SP for a leg division. Rather than paying the total amount of the HQ command points (5 for 3 Panzer) to put the entire Korps in attack supply. So the Germans will pay 4 rather than 5 points to put the 2 mobile divisions of 3 Panzer Korps in attack supply for the turn. 44 Jaeger will pay 1 more SP to put 100 Jaeger Division in attack supply as well.
The Soviets have no supply points to burn, so everyone becomes depleted.
Next up is Soviet Operations Phase. The Out of Command Control divisions move inside the command range of 9 Army. Since they are also depleted, they lose 1 movement point. The disrupted 106 Division cannot perform a regroup operation to remove its disruption since it is in an enemy ZOC. A disrupted unit cannot remain in an enemy ZOC either, so it must withdraw. The reinforcing division and brigade attempt to force march by rolling against their effectiveness rating, but fail so they move normally. The other units try to form a defensive line across the German line of advance. In depleted mode, they are -1 in ZOC ratings, so the Germans will be able to manoeuvre around them unless they are stacked, since two units with 0 ZOC rating are equivalent to 1 strength ZOC. Units that don't move have the option to entrench, but all Soviets are moving, so no entrenchments are dug.
The German Operations Phase begins with supply columns from Army Group South heading from the west edge of the board towards 1 Panzer Army HQ bring up 8 supply points for future turns. Next, 97 Jaeger division breaks down into 2 infantry regiments and an engineer battalion in order to hold the 3 Panzer Korps line of supply along the road. 100 Jaeger division is in attack supply, so it moves up to attack Barenkovo, a victory point location that now holds 3 cavalry divisions. The engineer battalion from 97 division joins it since attacking a town with an engineer (even in defensive supply) gives a +1 DRM. There is an effectiveness DRM in infantry-only combats in which the differential in attacker/defender effectiveness ratings is also used as a DRM. This gives the Germans a further +2, and a ground-support mission by the Luftwaffe chips in another +3, and von Kleist with the 44 Jaeger Korps HQ adds a +1. Both sides succeed in their effectiveness rolls so their primary combat factors are used and the odds are 2:1. The roll yields a result of DR1, meaning the defenders disrupt and retreat one hex. They have a chance to ignore the retreat if they make a morale (effectiveness) check against their rating of 2. They roll a 6, so they give up Barenkovo and the German engineer battalion advances into the town. On the right, the 3 divisions of 52 Korps move up but don't attack. Finally, 3 Panzer Korps activates with its 2 mobile divisions in attack supply and the reinforcing 16 Panzer in defensive supply.
60 Motorized sends its recon battalion around the disrupted 106 infantry division and the rest of the division moves into Barenkovo to attack. This uses 1 engagement point of the HQ's 6 EPs for a stack to manoeuvre before combat, and 2 EPs to attack with a single stack. The Soviet division fails its effectiveness roll as it is both disrupted and depleted, but suprisingly, so does the 60 Motorized, leaving the odds at 3:1. Modifiers are +1 for the leader at HQ, +1 artillery (60 division HQ has 1 artillery factor), +3 for the ground support aircraft committed to the attack. There is no effectiveness differential bonus, since that only applies to leg unit combats. Also, since this is a motorized division, it has no armour bonuses. The roll is 2 with a +5 DRM results in a DD, requiring the defender to pass a morale (effectiveness) check and retreat if it fails, disrupting in either case. Since the 106 has -2 for being already disrupted and -1 for being depleted, it automatically fails and routs. retreating an extra hex above the already mandated 1 hex. Mobile attackers may advance 2 hexes, so the 60 advances 1 regiment and 1 battalion 1 hex and another 2 hexes up the road. This advance does not cost any extra EPs.
Lastly, 3 Panzer Korps HQ begins another operation with a fresh 6 EPs; 14 Panzer division moves up the cleared road towards the next victory objective but is 1 hex short of being able to attack the Soviet tank brigade on the road, because it has to infiltrate through the ZOC of the 2 Soviet infantry divisions which costs an extra 2 movement points. Instead of attacking, since the division has an armoured recon battalion, a Recon in Force marker can be placed in the empty road hex ahead. This allows the Germans to trigger a counterrattack using any mobile units of the recon battalion's parent HQ if an enemy unit enters the hex. That is all that the Germans can do for now. The air units saved for support of 14 Panzer attacks are wasted - they could have been used to barrage targets before the Operations Phase but it is too late now.
This is the end of Turn 4. The next turn will be similar: a disrupted and depleted Soviet force trying to block the advance of a more effective and better supplied attacker. Only on Turn 6 will there be a Strategic Overphase which will allow the Soviets to roll for supply points and attempt a counterrattack with what force they have left. This is not a fun scenario for the Soviets; it merely gives the player an opportunity to practise the mechanics of the game before trying out the main event, which will give the Soviets some high-quality mechanized corps and Guards infantry divisions and enough supply to carry out offensives of their own.