This is the first in a series of occasional columns on experimental game mechanics and stray ideas for our favorite game system, the big E itself.

Straight from the Laboratory

The Europa laboratory concocts all sorts of experiments, including many monsters or curiosities that never see the light of playtesting, let alone publication in a game. It's not that these experiments are bad, it's just that there's only so much time to work on things, and other items get priority. This is particularly so for an experiment on a rule that already works well-especially if the experiment may have wild and unpredictable effects on already-published games. Low-odds overruns is a prime example.

Low-odds overruns have been suggested in various articles and EXchanges in this magazine over time. In brief, the standard overrun rule in Europa allows a force to brush aside insignificant resistance during the movement phase and continue to move and fight. Without it, a defender could deploy a cloud of 0- and 1-point units in front of the attacker's spearheads, thereby limiting the enemy advance to one hex per turn without losing lots of units. Low-odds overruns extend this idea further, allowing a strong force the chance to blast through minimal (although not entirely insignificant) opposition.

In theory, low-odds overruns would open up play and make things more freewheeling. In practice, it's unclear if the mechanic would actually improve play or unbalance it. Shall we experiment and see?

I've never liked most of the suggested low-odds overrun mechanics-they've been too complex or too wild in effect (or both). There is, however, a simple way to expand the existing overrun rule to handle low-odds overruns. See the overrun summary below for an overview.

Notes:

• c/m: combat/motorized.
• Total Elim: The units being overrun are completely eliminated and removed from play, even if they have cadres.
• Use GCRT: Use the ground combat results table to resolve the overrun attempt (see explanation below).
• X: An overrun is not possible at these odds for the indicated units.

Simply use the overrun rule as is (overrunning units must be in one hex and meet stacking requirements, etc.) with the following additions:

• Overrun Odds: Calculate the overrun odds just like combat odds, per the overrun rule. The only change is that overruns are now possible at odds less than 10:1.
• Overrun MP Cost: The overrun odds determine the MP cost each unit must spend to participate in the overrun, per the overrun MP cost column on the summary. For example, a German c/m unit overrunning an enemy unit must spend 2 MPs for a 10:1 overrun, 5 MPs for an 7:1 overrun, etc. As before, the overrun MP cost is in addition to the cost to enter the hex. Needless to say, if a unit doesn't have enough MPs to pay all MP costs for an overrun, it can't participate in the overrun.
• Use the Ground CRT: Overruns at 10:1 or more still result in the complete elimination of the units being overrun, per the standard rule. For odds of 9:1 or less, resolve the overrun using the ground combat results table, applying all die roll modifiers (for terrain, AEC/ATEC, etc.) as normal. Roll the die, find the result, and implement it per the combat rule (including any retreat and advance after combat). Note that armor, through AECA effects, can be especially effective in a low odds overrun, unless you're foolish enough to do something like sending in the tanks against a fortress stuffed with antitank weapons.
• After effects: If the overrun result was either Total Elim or DE, the units participating in the overrun can continue to rock and roll: they can continue to move, overrun, participate in combat in the combat phase, etc. If the result was anything else, the participating units have shot their wad and cannot move (or otherwise spend MPs) for the rest of the phase. In addition, if the overrun occurred in the movement phase, these units cannot attack during the following combat phase.

Example: A German c/m stack consisting of an 12-10 Pz XX and a 6-10 Mot XX start the German player turn adjacent to a Soviet 3-6 Rifle XX that's in a woods hex. The weather is clear; all units are in supply; there are no enemy ZOCs on the German units except that of the 3-6 division itself. The German stack attempts to overrun the Soviet unit. The overrun odds are 6:1 (18:3); the MP cost for each overrunning unit is 2 to enter the hex and 7 for the overrun. The ground CRT is used: odds are 6:1, with a +2 die roll modifier for the overrun attack (+3 for full AECA; -1 for woods).

The die roll is 3 and is modified to a 5, for a result of DE. The Soviet unit is eliminated; the overrunning units may advance into the hex, if the German player wishes. The overrunning units each have 1 MP remaining and thus can continue to move. They can attack in the combat phase and move again in the exploitation phase. Note 1: Had the overrun die roll been a 1 (and thus modified to a 3), the overrun result would have been DH. The Soviet unit would still be eliminated, and the German units could advance into the hex.

Since the overrun did not result in a DE, however, these units could not move further in the movement phase or attack in the combat phase. (They could move in the exploitation phase.)

Note 2: Had there been another Soviet division nearby that exerted a ZOC into both the German units' hex and the Soviet 3-6's hex, the German units wouldn't have been able to overrun at 6:1, since the cost to move through an enemy ZOC would have raised the total MP cost to 11 MPs (2 for woods, 2 for the ZOC, and 7 for the overrun), more than the units have available.

Analysis

Although the low-odds overrun rule doesn't seem to be a radical revision of the existing system, it may have profound impact on play. Mostly, low-odds overruns favor high-MP high-AECA stacks, since they can smash and advance. For other units, the high MP cost and the likelihood of a non-DE result means they are simply getting to take their combat phase a bit early. This is significant, however, as even if the overrunning units themselves are halted in their tracks, other nearby forces can take advantage of any holes blasted in the enemy line.

The rule's implications for Fire in the EastIScorched Earth are interesting. In 1941, the extreme case is that the German 60-strength panzer stack can attempt to overrun a Soviet force of up to 12 defense points-as long as it starts adjacent, overruns into clear terrain, and doesn't move through/out of enemy ZOCs.

The extreme case is, well, extreme and will rarely come up. In practice, however, two panzer corps can work together to leverage open a two-hex deep Soviet line. Assume clear terrain but having to move through Soviet ZOCs everywhere: The first panzer corps (or even a strong infantry corps, depending upon the circumstances) can hit the front line with a low-odds overrun, with a very good chance of opening up the hex. The adjacent panzer corps can now enter the cleared-out hex (3 MPs; 1 for the hex and 2 for the ZOCs) and have enough MPs to overrun the second line at 8:1 (7 MPs; 1 for the hex, 2 for the ZOCs, and 4 for the 8:1 overrun). If that overrun gets a DE, then the stack can hit a third line, in the combat phase- a powerful punch.

The actual effects of this on FitEISE are not clear. The Soviets would have to build lines with 11-13 defense points per hex to overrun-proof their front line everywhere. This is probably not possible most of the time, and almost certainly wouldn't leave enough to form an overrun-proof second line behind the first in most places-only the absolute critical areas could get this treatment.

Possibly, a spaced defense may work: a forward line to absorb the initial impact of the enemy, with a second line (possibly double deep) not adjacent but further back so that the enemy blows off MPs reaching it, lessening the likelihood of low-odds overruns. That's one theory. Another one is that low-odds overruns may be too tough for the Soviets to handle, making the runaway defense the plan of choice for non-critical areas.

So, Now What?

Help me out. I need to build up a database of experience with low-odds overruns so that I can see how they work in practice. There are three important campaigns to test: FitEISE (see the above analysis), Western Desert (it's difficult to assess what impact low-odds overruns will have on a high mobility, low unit density game), and the 1944 campaign scenario of Second Front (do the Allies munch their way to Berlin too quickly once they break out?).

Your help here is crucial. Normal playtest channels would be a case of too few attempting to do too much. So if you are at all inclined to try out this rule (whether you like it, hate it, or don't care), go ahead and try it out. Keep a few notes tracking how the rule affected the game: what happened in play, the outcome of the game, and what, if any, effect it had on the players' approach to play of the game. Send in your notes to EXchange. If sufficient information on low-odds overruns comes in, I can assess the impact on the system and decide whether or not the rule should ever leave the laboratory.

Skeletons in the Closet

Anything as complex as Europa will have quirks and anomalies hidden in the game mechanics-and I know where some of the bodies are buried. Here's one on the ground CRT: Which attack would you rather make: a 1:1 W), or a 1.51 with no modifier? The combat results are almost identical, but there's a 1/6 chance at 1:1 (+1) of an HX, while at 1.5:1 there's a 1/6 chance of an EX instead. Clearly, you'll take fewer losses at 1:1 (+1). This can be significant (slightly) for the Soviets, if they are trying to bleed the Germans through low-odds attacks.

1.5:1 even up vs. 2:1 (-1) is also interesting. In effect, an AR and a DR at 1.51 become an AH and an HX at 2:1 (-1). This time, for the Soviets pursuing an attrition strategy, 2:1 (-1) is better. On average over a series of attacks, it turns a net AS (AR and DR) at 1.51 into a net EX (AH and HX) at 2:1 (-1).