Steps to do:
- 1. Start up Panzerkreig (difficulty doesn't matter nor does importing cores or specialization).
2. Go into the first mission.
3. Pick the option to customize your own core force. Pay attention to how much requisition points (RP) you have. You should have 1065 RP (965 RP if you import a core and transfer RP to the SS, but we didn't).
4. Buy and deploy three 17 cm K 18 artillery guns with mounts. All three cost 290 RP each with mounts. 290 * 3 = 870 RP. That subtracts from your total leaving you with 195 RP left.
5. Buy and deploy a single 7.5 cm LeIG 18 artillery gun with no mounts. That is 50 RP for the gun. So, you now have 145 RP left.
6. Buy and deploy a single German Engineer '41 with no mounts costing 30 RP. You should have 115 RP remaining.
7. Now, go into the upgrade tab for the LeIG 18 gun and select it to upgrade to the 15 cm sFH 18 gun with a mount.
8. Look at the screen for a bit. You should notice that you have enough RP to upgrade to the 15 cm itself, but you don't have enough to pay for the mount which cost 40 RP. Yet, the "Upgrade" button is not blocked. Click to upgrade.
9. Acknowledged that the upgrade took place; the LeIG 18 should be the sFH 18. Take a glance at your total RP. It stayed at 115 RP even though you clearly made an investment.
10. Resell all your units and you'll see 1205 instead of 1065. You just cheated 140 extra RP. Jackpot!
You can repeat this as much as you like. The main idea to keep in mind repeating this is to always have a LeIG 18 gun with no mount deployed and your current RP stockpile to be > 100 RP but also < 140 RP when upgrading.
I would submit pictures if I figured out how. I'm a new member to the forum.
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