When you cast that spell, Inexorable Tide triggers, putting one +1/+1 counter on Arcbound Reclaimer and at least two additional artifacts you control.
Activate The Great Henge by tapping it, adding and gaining 2 life.
Activate Krark-Clan Ironworks by sacrificing The Great Henge, adding CC.
Activate Arcbound Reclaimer by removing a +1/+1 counter from it, putting The Great Henge from your graveyard on top of your library.
Activate Iron Spider's last ability by paying 2 and removing two +1/+1 counters from artifacts you control, drawing The Great Henge.
Repeat.
This clever artifact loop lets you repeatedly cast, sacrifice, and recur The Great Henge to generate an endless storm of triggers and card draw. As you cast the spell, Inexorable Tide capitalizes on the action to passively proliferate your counters, helping to fuel Arcbound Reclaimer and Iron Spider, Stark Upgrade. Krark-Clan Ironworks then provides the necessary mana by dismantling The Great Henge, allowing Arcbound Reclaimer to tuck the enchantment back onto your library. Finally, Iron Spider, Stark Upgrade uses its activated ability to burn through counters and draw The Great Henge right back into your hand, ready to start the cycle anew.