Forge

The Forge is unlocked when you reach the Underground City, at 303km. Here you can forge Gems to improve your Weapons.

You can use the shortcut "G" (Gem Forge) to reach it. This is very useful when using timelapses repeatedly and forging short-timed gems.

Forge

Forge levels

Level	Max Queue	Cost for next level
1	6	$1 Trillion & 16 Oil & 5 Building Materials
2	10	$4 Trillion & 100 Oil & 15 Building Materials
3	20	$40 Trillion & 2,000 Oil & 30 Building Materials
4	30	$400 Trillion & 4000 Oil & 80 Building Materials
5	40	$5 quadrillion & 6,000 Oil & 160 Building Materials
6	55	$100 quadrillion & 8,000 Oil & 320 Building Materials
7	75	$1 Quintillion & 11,000 Oil & 500 Building Materials
8	85	$50 Quintillion & 15,000 Oil & 750 Building Materials
9	100	$1 sextillion & 20,000 Oil & 1000 Building Materials
10	120	Maxed

Gems

Crafting Time

After the v0.45 update the gems are reworked and made automated if you allocate workload on them. Depending on the workload the time for crafting varies with more workload resulting in faster crafting speed$$Gem\ Time=(Slot/Workload)*(BaseTime/60)$$

	Red	Blue	Green	Purple	Yellow
Slot	1	2	3	4	6
Base Time( hours)	0.05	3	12	20	280

Say you want to make gem1, but it takes gem2, and you don't have it.

and assuming that if you start making either with the correct workloads, you will never run, which is probably easy to be sure of .. ( just by inspection..).

Then look at the dependency .. define N as it N gem2 to make gem1,

and define Time1 is how long one workload takes to make gem,

and Time2 is how long one workload takes to make gem1,

and WL1 is the work load to set to gem1, and WL2 is the work load to set to gem2.

and MWL is maximum workload we can assign to both or either gem 1 and/or gem2..

then the total time to make that many additional gems of gem1 and gem2, assuming no dependency issues, would be Time1 + Time2* N.

Then the ratio of WL2 to WL1 is Time2 *N / ( Time1 + Time2* N)

and WL2 should be Time2 *N / ( Time1 + Time2* N) * MWL

WL1 should be the rest, or Time1 / ( Time1 + Time2* N) * MWL

Then if you wanted to let it run making gem1 and gem2 3 months , you could let it run with those workloads, and not have much inefficiency, even if you started with zero gem2 , despite gem1 requiring gem2 at the rate of N gem2 per gem1. (but that was only if the supply of other depencies was "obviously" no worry ... that is, they were coming in fast enough or of large enough supply, relative to the production run... )

if workloads WLG1 and WLG2 must be in the ratio of

TIme1 (

Time in minutes for one gem, for each workload and gem.

Workload	Red	Blue	Green	Purple	Yellow
1	3.00	180.00	720.00	1200.00	16800.00	MINUTES
2	1.50	90.00	360.00	600.00	8400.00	MINUTES
3	1.00	60.00	240.00	400.00	5600.00	MINUTES
4	0.75	45.00	180.00	300.00	4200.00	MINUTES
5	0.60	36.00	144.00	240.00	3360.00	MINUTES
6	0.50	30.00	120.00	200.00	2800.00	MINUTES
7	0.43	25.71	102.86	171.43	2400.00	MINUTES
8	0.38	22.50	90.00	150.00	2100.00	MINUTES
9	0.33	20.00	80.00	133.33	1866.67	MINUTES
10	0.30	18.00	72.00	120.00	1680.00	MINUTES
11	0.27	16.36	65.45	109.09	1527.27	MINUTES
12	0.25	15.00	60.00	100.00	1400.00	MINUTES
13	0.23	13.85	55.38	92.31	1292.31	MINUTES
14	0.21	12.86	51.43	85.71	1200.00	MINUTES
15	0.20	12.00	48.00	80.00	1120.00	MINUTES
16	0.19	11.25	45.00	75.00	1050.00	MINUTES
17	0.18	10.59	42.35	70.59	988.24	MINUTES
18	0.17	10.00	40.00	66.67	933.33	MINUTES
19	0.16	9.47	37.89	63.16	884.21	MINUTES
20	0.15	9.00	36.00	60.00	840.00	MINUTES
21	0.14	8.57	34.29	57.14	800.00	MINUTES
22	0.14	8.18	32.73	54.55	763.64	MINUTES
23	0.13	7.83	31.30	52.17	730.43	MINUTES
24	0.13	7.50	30.00	50.00	700.00	MINUTES
25	0.12	7.20	28.80	48.00	672.00	MINUTES
26	0.12	6.92	27.69	46.15	646.15	MINUTES
27	0.11	6.67	26.67	44.44	622.22	MINUTES
28	0.11	6.43	25.71	42.86	600.00	MINUTES
29	0.10	6.21	24.83	41.38	579.31	MINUTES
30	0.10	6.00	24.00	40.00	560.00	MINUTES
31	0.10	5.81	23.23	38.71	541.94	MINUTES
32	0.09	5.63	22.50	37.50	525.00	MINUTES
33	0.09	5.45	21.82	36.36	509.09	MINUTES
34	0.09	5.29	21.18	35.29	494.12	MINUTES
35	0.09	5.14	20.57	34.29	480.00	MINUTES
36	0.08	5.00	20.00	33.33	466.67	MINUTES
37	0.08	4.86	19.46	32.43	454.05	MINUTES
38	0.08	4.74	18.95	31.58	442.11	MINUTES
39	0.08	4.62	18.46	30.77	430.77	MINUTES
40	0.08	4.50	18.00	30.00	420.00	MINUTES
41	0.07	4.39	17.56	29.27	409.76	MINUTES
42	0.07	4.29	17.14	28.57	400.00	MINUTES
43	0.07	4.19	16.74	27.91	390.70	MINUTES
44	0.07	4.09	16.36	27.27	381.82	MINUTES
45	0.07	4.00	16.00	26.67	373.33	MINUTES
46	0.07	3.91	15.65	26.09	365.22	MINUTES
47	0.06	3.83	15.32	25.53	357.45	MINUTES
48	0.06	3.75	15.00	25.00	350.00	MINUTES
49	0.06	3.67	14.69	24.49	342.86	MINUTES
50	0.06	3.60	14.40	24.00	336.00	MINUTES

Pre v0.45 page

Gem cost

Gem and Catalyst

Item	Time	Slots	Material 1	Material 2	Material 3	Oil	Cost
Red Gem	10 Min	1	x2,000 Red Diamond
Blue Gem	30 Min	2	10k Blue Obsidian			x1 Oil	$10 Billion
Green Gem	4 Hour	3	10k Coltan	10k Californium		x4 Oil	$30 Billion
Purple Gem	16 Hour	4	25 Red Gem	25 Blue Gem	x25 Polonium2	x16 Oil	$500 Billion
Yellow Gem	48 Hour	6	25 Red Gem	25 Green Gem		x200 Oil	$1.5 Trillion
Catalyst	5 Min	1	150 Uranium2	75 Plutonium2		x4 Oil	$5 Billion

Forge Upgrades

Depending on your play style, you may not need to upgrade the Forge to maximum. The Gems stop being useful when you max all of your weapons, and this may happen sooner.

Level	Workload Slot	Cost for next upgrade
1	6	$1 Trillion & 16 Oil & 5 Building Materials
2	8	$4 Trillion & 100 Oil & 15 Building Materials
3	12	$40 Trillion & 2,000 Oil & 30 Building Materials
4	20	$400 Trillion & 4000 Oil & 80 Building Materials
5	25	$5 quadrillion & 6,000 Oil & 160 Building Materials
6	30	$100 quadrillion & 8,000 Oil & 320 Building Materials
7	35	$1 Quintillion & 11,000 Oil & 500 Building Materials
8	40	$50 Quintillion & 15,000 Oil & 750 Building Materials
9	45	$1 Sextillion & 20,000 Oil & 1000 Building Materials
10	50	Max Level

Catalyst Use

Each catalyst, when applied to a current craft, will reduce the remaining time for the craft by 20%, stacking multiplicatively, at the cost of using one more slot.

The next section explain this calculation in detail, and then there'll be a table for times, but in short, catalyst should be used:

• Green gems: Only if using 4+ at a time
• Purple gems: If using 2+ at a time
• Yellow gems: Always, as much as wanted

Isotopes efficiency

On the line of don't sell isotopes, when you start using catalysts in earnest, you may miss the costs in isotopes. Each Catalyst uses 150 Uranium-2 and 75 plutonium-2. While this is not much in absolute terms, the full Earth production is around 325/hour for each of these isotopes. So every 2 catalysts, you're using 1 hour of your mine's isotopes production. Much more, if you haven't completed Earth yet.

Thus, while catalysts may lower time to almost arbitrary amounts (a Yellow Gem, base 48h, is reduced to 42 min by 19 catalysts, to less than 5 minutes by 29 catalysts, and to 9 seconds by 44 catalysts) you are in a very real way gaining time by burning a limited resource. And at some point, you're not even gaining much time at all.

If you've already reached the reactor, you can partially fix this with tactical use of your fuel rods, which allows you to basically convert U-1 into the rest of isotopes. However, the efficiency of conversion is only 18% at best. So, even considering the ~3500/h production of U-1, after converting to U-2 you only get at most thrice the world's production, i.e. one hour of production for every 6 catalysts. It's up to you to decide if the time and attention needed to juggle this is worth it.

In summary, when the tables below indicate that using two additional catalysts will lower the crafting time by less than 1 hour, you start burning more isotopes than the time you're gaining. It's up to you to balance time efficiency vs. resource efficiency. The revised recommendation from the above would be:

• Green gems: Up to 6 catalysts per green gem.
• Purple gems: Up to 10 catalysts per purple gem.
• Yellow gems: Up to 15 catalysts per yellow gem.

Time efficiency calculation

If you are trying to determine the most efficient use of time, you will want to calculate how many "slot-minutes" are used by a recipe. Building a green gem with no catalysts runs for 240 minutes and uses 3 slots, for a total cost of 720 slot-minutes. Building a green gem with 10 catalysts runs for 25.75 minutes and takes 13 slots, for a cost of 335 slot-minutes. Building the catalysts takes 5 slot minutes each, or a total of 50 slot minutes for 10 catalysts. The overall cost is 385 slot minutes.

Red and Blue gems (and of course, catalysts themselves) should never be built with catalysts. Once you start adding 5 minutes per catalyst for the cost of making the catalysts, the overall efficiency goes down with every catalyst you add. Not only that, but you increase the slots more than it's worth. E.g. for Blue, the first catalyst reduces the time to 24 min, but increases slot use to 3. Slot/min was 30*2 = 60. Now it's 24*3+5=77. For the next catalyst, the actual slot/min is 87, and it gets worse the more you add.

For Green gems (3 slots), the first three catalysts worsen the time (base is 240*3 = 720, with 1 catalyst is 192*4+5=773), but from the fourth catalyst onwards this improves over the original (708 slot-min for 4 catalysts, 483 for 8 catalysts, etc.). Of course, making green gems one at a time requires more babysitting, so I think it is up to each person to decide if it is worth it or not. If the other costs (oil, Pu, and U) are not important (at some point of the game, they aren't), then it may be worth it

For Purple gems (4 slots), the first catalysts worsen the time a little (base is 960*4 = 3840 slot-min, 1 catalyst leaves it at 3845), but from there it's all improvement (3165 with 4 catalysts, 1972 with 8 catalysts, etc.).

For Yellow gems (6 slots), catalysts are always worth it.

Babysitting tables

Once it's worth to use a certain number of catalysts, it's worth (in time) to fill your Forge with them and make gems one at a time. However, keep in mind:

• Babysitting: It's bothersome to check the Forge every N minutes (specially if you're not playing active).
• Timelapse: The less minutes it takes, the more minutes you waste when you get a fixed time timelapse (a classical problem when crafting Catalysts and Red Gems).
• The time and attention needed to craft the Catalysts themselves (both timelapse and babysitting problems)
• The isotopes consumption (specially if applied to Green Gems).

As you can see, the time quickly becomes negligible. Tables show # of catalysts needed to go down to 10 min. Background is red for catalyst combinations that worsen efficiency.

Green Gems	Purple Gems	Yellow Gems
# Cat Min Hour Slot-min 0 240 4,00 720 1 192 3,20 773 2 154 2,56 778 3 123 2,05 752 4 98 1,64 708 5 79 1,31 654 6 63 1,05 596 7 50 0,84 538 8 40 0,67 483 9 32 0,54 432 10 26 0,43 385 11 21 0,34 344 12 16 0,27 307 13 13 0,22 276 14 11 0,18 249	# Cat Min Hour Slot-min 0 960 16,00 3840 1 768 12,80 3845 2 614 10,24 3696 3 492 8,19 3456 4 393 6,55 3166 5 315 5,24 2856 6 252 4,19 2547 7 201 3,36 2250 8 161 2,68 1973 9 129 2,15 1720 10 103 1,72 1493 11 82 1,37 1292 12 66 1,10 1116 13 53 0,88 962 14 42 0,70 830 15 34 0,56 717 16 27 0,45 620 17 22 0,36 539 18 17 0,29 470 19 14 0,23 413 20 11 0,18 366	# Cat Min Hour Slot-min 0 2880 48,00 17280 1 2304 38,40 16133 2 1843 30,72 14756 3 1475 24,58 13286 4 1180 19,66 11816 5 944 15,73 10406 6 755 12,58 9090 7 604 10,07 7887 8 483 8,05 6805 9 387 6,44 5843 10 309 5,15 4998 11 247 4,12 4261 12 198 3,30 3622 13 158 2,64 3073 14 127 2,11 2603 15 101 1,69 2203 16 81 1,35 1863 17 65 1,08 1577 18 52 0,86 1335 19 42 0,69 1133 20 33 0,55 963 21 27 0,44 822 22 21 0,35 705 23 17 0,28 608 24 14 0,23 528 25 11 0,18 462

Note: if you don't care about isotopes use, or need to upgrade weapons fast, the catalyst required for maximum efficiency (in slot-min) for gems at different forge levels are (counting the time it takes to make the catalyst):

Gem Efficiency

Forge Level	Green Gems	Purple Gems	Yellow Gems
1	0 (720 slot-min)	2 (3696 slot-min)	0 (17280 slot-min)
2	5 (654 slot-min)	4 (3165 slot-min)	2 (14756 slot-min)
3	9 (432 slot-min)	8 (1972 slot-min)	6 (9090 slot-min)
4	17 (193 slot-min)	16 (620 slot-min)	14 (2603 slot-min)
5	22 (154 slot-min)	21 (326 slot-min)	19 (1133 slot-min)
6	25 (150 slot-min)	26 (217 slot-min)	24 (528 slot-min)
7	25 (150 slot-min)	31 (188 slot-min)	29 (301 slot-min)
8	25 (150 slot-min)	32 (187 slot-min)	34 (228 slot-min)
9	25 (150 slot-min)	32 (187 slot-min)	38 (216 slot-min)
10	25 (150 slot-min)	32 (187 slot-min)	38 (216 slot-min)

IMPORTANT: Once you reach a certain amount of catalysts, using more catalysts worsens efficiency, even for yellow gems. If you have extra slots, you can use them to craft catalysts/red/blue gems.