Glaring Fleshraker's first ability triggers, creating a 0/1 Eldrazi Spawn creature token.
When the Eldrazi Spawn enters, Glaring Fleshraker's second ability triggers, dealing 1 damage to each opponent.
When Metallic Sliver enters, it and Glaring Fleshraker's second ability trigger.
Resolve the Metallic Sliver trigger, dealing 1 damage to target player or planeswalker and causing you to gain 2 life due to its ability and lifelink.
Resolve the Glaring Fleshraker trigger, dealing 1 damage to each opponent.
Activate Metallic Sliver by paying 2 life, returning it from the battlefield to your hand.
Activate the Eldrazi Spawn by sacrificing it, adding C.
Repeat.
This clever loop transforms an unassuming metallic drone into a lethal engine of attrition by leveraging a web of overlapping Sliver abilities and Eldrazi triggers. With Lavabelly Sliver and Syphon Sliver granting every entering Sliver both a direct drain effect and lifelink, simply casting Metallic Sliver triggers multiple instances of damage while keeping your life total safely out of reach. Glaring Fleshraker acts as the ultimate catalyst here, supplying the colorless mana required to recast the loop by generating an Eldrazi Spawn token every time Metallic Sliver is cast, while also stacking additional damage onto each opponent whenever any creature or token enters the battlefield. Finally, Hibernation Sliver provides the safety valve to return Metallic Sliver directly to your hand for just 2 life—an expense easily offset by your lifelink gains—allowing you to repeat the entire cycle indefinitely.