[2.4] Bonegrinder - Heartbound Loop Molten Shell

I have been tinkering around to make a Heartbound loop build HC viable for a while. It worked quite well, until I died on lvl 69 :D Since I don't have to time to farm enough currency for the Items on HC in the next weeks, I played it on Softcore a bit more (lvl 73), so the endgame is not tested. I think it should also be endgame viable.

Overview (Sewer map)
Vaal Pyramid bosses (all spawned before combat)
Merciless Izaro 1
Merciless Izaro 2
Merciless Izaro 3

The main damage source is molten shell, which is procced mainly by Heartbound Loop (HBL). HBL is mainly fed by skeletons, which are cast on crit through cyclone. Also CWDT skeletons are cast and Scold's Bridle is another source of damage to proc Molten Shell. These hits proc Juggernauts 20% chance to gain endurance charge when hit quite often, so that a constant stream of endurance charges is obtained. These endurance charges are consumed with immortal call, which mitigates all damage from Scold's and Heartbound Loop. So 100% of physical damage work towards Molten Shells threshold. Even when no damage is received, it still counts as hit, so further endurance charges are created. In addition Vengeance is also procced by 0 damage hits from Scold's and HBL, which always crits because of Trypanon and is therefore linked with Cast on Crit, to proc Flamability, Fire Golem and Immortal Call. Last but not least the Kingsguard armor throws in 100 health recovered per consumed endurance charge.

+ very tanky
+ everything happens automatically (skeletons, molten shell, immortal call, curses, golem, blood rage,
heal)
+ similar to Vaal Molten Shell builds, but no hassle with duration and souls
- 2 expensive league-specific items necessary
- higher killspeed is possible with other builds at same price level

As one can see there is a lot of improvement possible.

this thread has a lot of information about the mechanics and how this build came to my mind: Other Thread

The biggest room for variations is the use of mana pool. I have tried auras like determination or purity of fire/ice, also Blasphemy for curses, with Doedre's Danning 2 curses would be possible, taking elemental weakness together with flammability will further increase the damage output. I have used Mind over Matter in the end for 30% damage taken goes to mana. I died to magic sea witches. Cycloning into them straight was not a good idea. With MoM I do survive these occassions now, but my life drops really low. Another possibility is to get Anger and/or Heralds, I did not find the damage increase worth it (15k -> 16k damage for 50% reservation).
Also Fortify can be included, for even more tankyness. Maybe second slot some dagger with whirling blades might be the best option, whirl in, get fortify, switch weapons cyclone.