With the testnet explorer it's a real pain manually tracking transactions
I had some success tracking it, but didn't chase too far because of the testnet explorer not making it any easier. With the chainz.cryptoid.info explorer it used to be much easier, but they don't have one for testnet.
Lets call 731fe63009611a07cfaae4b88d0c8608eac74217fc0c38eceb1272f9c7c6484c Tx 0).
The Txs that lead to your Tx:
1) 7cb9b81c5befd95f38ea11e21157aeaafcfe9c5981da8c5ff41d071ea28881e0 - sends 400.00000004 DRK to 0)
2) 41ca6cde66e4ae880a43ffee3eb76f5c50e623f1b9c0d285ba90102f41486daa - sends 90.00000009 DRK to 0)
3) 0299644af5ae2c275043a1d351e0187197fe315e1c7fffb2420a409649e1accf - sends 0.10000001 DRK to 0)
4) 9fd30dd2cb0a52fe0834a0c8c93a416237d1f05c5e0b7ad5dc4dd053bd3f6235 - sends 500.00000005 DRK to 0)
5) 9a559dcb54fb7196b2246951fddf7c7c0072add05f50475ff2f7a57aba97a61b - sends 100.00000001 DRK to 0)
From there, I found
6) 10e98361fa86832c03153ba5a672188dc4b62a5e5ebb92b7d0caa5ba3c27cf1d - This transaction sends 778.0712995 DRK to y3r2VcndLy14d6KQEm3ac5u21imVjHN9CW, which is then used in 2) to pay for 0). I know this because the other inputs of 2) are not big enough, leaving only the 778.0712995 DRK output as the funds in question. Also, 2) has an output of 668.07129939 DRK, which is, when substracted from 778.0712995, 110,00000011DRK or 11x 10.00000001. This adds extra evidence those 2 are related.
What is interesting is, 6) not only leads to 2, but also to 4) and 5).
Goind further, these 778.0712995 DRK can be traced to 7) 20f3fda7cb19602cf581fc7c2464a34c5372c94ac88e635d9e82c35898520ce7 - In a similar fashion we have no other input that is big enough to be corelated with our output that has already been tied to Molis Tx. It's an input of 883.00000019 DRK in 6), coming from 7).
Interestingly enough, 6) only has a total input of 936.64272834 DRK. However, it also sends 70 DRK to 4), which is more than the leftover if we substract the big input from the total input. This meant, that the 883.00000019DRK is not only related to 2), but also to 4), adding additional evidence that we are on the right path.
6) also sends 40 DRK to 5), but this is not enough to exceed the leftover, so we cannot be certain that it's directly coming from the 883.00000019 DRK.
Looking at the inputs of 7), we can see a total input of 1023.0000015 DRK. Looking for a big input that can be tied to our big output of 883.00000019 DRK does not work this time since the biggest single input is 100.00000001 DRK. However, there is a more than the leftover (which is 139.99999996 DRK) total input from a single Tx, which means that we can be 100% sure that at least some of our funds come from this Tx. Inspecting the Tx, we can see 810.00000018 DRK coming from that Tx, leaving the difference of 73.00000001 DRK we can look for in the other transactions (because of the 1 duff at the end of this amount and the fact that this is not enough to properly DS-Denominate this amount, I think it is highly likely that at least one of the non DS-denominated inputs is related to the 73.00000001 DRK. However, since we already identified where most of the DRK came from, we will persue them first and maybe come back later).
This leads us to 8) - c9274a038b2253633bbf0b4c8f932a1838b8f4e352a9a5899034e0dcc95e883a - The Tx that send 810.00000018 DRK to 7).
This is where it gets interesting since the only non-DS-denomination outputs we have are 2x 80.0000008 DRK. This is interesting and means that we can probably count out 16 x 10.00000001 from the input list as not related to out funds (since we didn't have any 80.00000008 DRK inputs in 7). This makes life a bit easier, but still not easy since this time we do not have and other non-DS denominations.
From here on, one could look for inputs adding up to 810.00000018 DRK coming from as few Transactions as possible, in the best case scenario (for tracking purposes) this would be a single Tx.
If this does not lead anywhere, one could go back to the 73.00000001 DRK from 7) and keep going or go back to 1) or 3), which we haven't talked about at all.
As I said, its a real pain using the testnet explorer to manually do all this, which is why I am doing to stop here.
I conclude:
Moli said it was an 8 rounds DS Tx.
1), 2), 3), 4) and 5) therefore belong to DS round 8
therefore 6) belongs to DS round 7,
7) belongs to DS round 6
and 8) belongs to DS round 5.
We have been able to track a part of the funds over 3 DS rounds to DS round 5 and have then stopped chasing, while also admitting that with 8), things get a little more difficult.
While not having traced the the funds all the way back to its origin address, we have found out that there are different DS Txs which provide a different level of anonymity. I wish there would be more Txs like 8) and less Txs like 6), which making the linking of the bit input to the big output an easy task.
