Ah yes.
Depends. I specialize in Annihilate, and I take the following strategy(s).
=Phase 1:Blockade-First 3 pioneer squads are sent to immediately block all choke points.
-1 of the pioneers is to retreat back to HQ to start on a Wehrmacht Quarters and (If you want it so badly) a KraftKramp Centre.
-The other 2 are ordered to work backwards with capturing, starting with points closest to them going towards Allied HQs.
=Phase 2:PrepareAt this point, I like to secure choke points. Even if they are blocked, early Engineers can cut wire and sandbags.-Once your Quarters is up, start producing Volks,MG,Volks,MG, Volks, etc. Don't worry about Snipers at the moment, and Motorbikes arn't useful unless you need to counter a pesky sniper.
-Get your Volks to the front lines ASAP. CPUs like to counter attack and try to blow up your tank traps and wires with grenades.
-MGs, get them in Buildings or in heavy cover NEAR chokepoints.
-Use Pioneers to start building bunkers, equip them with MGs.
--(As soon as you can, if you get 125 munitions, don't think twice about a goliath for heavy chokepoints like Bridges. All you have to do is cut wire and your Goliath can slip through tank traps. It can also camoflage like a sniper in heavy cover)
-You should already be in skirmish phase, call back a pioneer squad to build a Kreig Barracks. Once that's up, Make AT guns and Mortar. Don't worry about Grenadiers unless you feel confident that they can replace Volks. If you panic and make grenadiers to counter enemy attacks you are just wasting Manpower.
=Phase 3:Lockdown-Secure any High or Medium Fuel and Munitions points.
-If you haven't started to vet, begin now. Infantry and Tanks are more expensive, and most of your early-mid units are Support and Vehicle. By this time I have about a Vet 1 for Vehicle and Infantry, and a vet 2 for Support units. You can vet tanks a bit later.
-If you have not, build your Sturm Armory.
--Depending on your defensives, if it is going well, begin to make Pumas and StuGs.
--If your defensive is constantly bombarded and infiltrated, make Nebelweffers. Vet 1 Support will allow them to travel very fast, and Vet 3 allows a 45 second reload
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At this stage, my defensive construction is complete, and I begin to build on a offensive.
=Phase 4:Assualt-If you have any Volks that arn't being used, direct them to go to the enemy HQ. They will eventually die. You'll need the population space.
-Any StuGs or Pumas you have, send them in to clear a path.
-Vet to Tank 1 (2 and 3 are preferred, as Vet 2 can suppress infantry and 3 can give huge armor bonuses).
-Depending on your enemy's selection of playing, go with one of the following:
--Ostwind:If the enemy constantly has infantry blobs, these are a good solution.
--Panzer IV: Good for basic anti-tank and Anti-Anti-Tank measures. Well suited for any combat situation, I would go with this if you are unsure of your enemy's approach. (XD)
--Panther: Use these if enemy tanks are a constant problem. Don't make these if you see 2 Shermans. Make these if you see 5 Shermans. THEN you have a problem.
-Your StuGs will have made a nice path for annihilation
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-For base destruction, make 2-3(Minimum) squads of Grenadiers. Equip them each with 2 Panzershrecks.
Warning! This process can take a long time, if your confident your Panzers and Panthers can survive 5-10 minute base assualts then skip this step, but otherwise this is necessary!
-For the Grenadiers, get a Halftrack for transportation around the MG bunkers.
=Phase 5:Annihilate!-Finish the enemy off by sending your tanks and your (Optional) halftrack with your panzershrecks inside. Make sure you have the resources to rebuild 1/2 of your assualt force in-case things go south.
-Head straight for the enemy HQ. Don't worry about units that are in the middle of the map. They'll retreat to base when they realize it's being destroyed.
-Upon arrival, order your grenadiers out, and order them ALL to attack the same building. 4-6 panzerschrecks are extremely powerful against buildings, and faster to reload than Panthers and Panzers.
-Enemy base will most likely be dead in 3-4 minutes.
*Note* If your assault doesn't go well, begin to rebuild when you have the feeling your tanks are going to die soon. This way you can continue your assault if all units die.
I hope this helped!