Declare Delina and Lightning Runner as attackers, triggering Delina twice and Lightning Runner once.
Resolve a Delina trigger, creating at least one token copy of Reservoir Walker that enters the battlefield tapped and attacking.
When the Reservoir Walker token(s) enter the battlefield, they trigger, causing you to get at least {E}{E}{E} and gain at least 3 life.
Repeat from step 2 for the remaining Delina trigger.
Resolve the Lightning Runner trigger, causing you to get {E}{E} and pay eight {E} to untap all creatures you control and to get an additional combat phase after this one.
At the end of your combat phase, each creature token created by Delina triggers, exiling themselves.
Repeat each combat phase.
Once you have infinite {E}, you may target any other creature(s) you control.

Infinite combat phases

Infinite copies of creatures you control

Infinite creature tokens

Infinite energy counters

Infinite ETB

Infinite lifegain

Infinite lifegain triggers

Infinite LTB

Infinite mana creatures you control can produce

Infinite untap of creatures you control

Delina, Wild Mage

Lightning Runner

Harmonic Prodigy

Reservoir Walker

Declare Delina and Lightning Runner as attackers, triggering them each twice.
Resolve a Delina trigger, creating at least one token copy of Reservoir Walker that enters the battlefield tapped and attacking.
When the Reservoir Walker token(s) enter the battlefield, they trigger, causing you to get at least {E}{E}{E} and gain at least 3 life.
Repeat from step 2 for the remaining Delina trigger.
Resolve the Lightning Runner triggers, causing you to get {E}{E}{E}{E} and pay eight {E} to untap all creatures you control and to get an additional combat phase after this one.
At the end of your combat phase, each creature token created by Delina triggers, exiling themselves.
Repeat each combat phase.
Once you have infinite {E}, you may target any other creature(s) you control.

Wulfgar of Icewind Dale

Activate Audacious Reshapers by tapping it and sacrificing Reservoir Walker.
When Reservoir Walker dies, Mortuary triggers, putting Reservoir Walker on top of your library from your graveyard.
Resolve the Audacious Reshapers ability, revealing Reservoir Walker from the top of your library, then putting it onto the battlefield and dealing 1 damage to you.
When Reservoir Walker enters the battlefield, it and Intruder Alarm trigger.
Resolve the Intruder Alarm trigger, untapping all creatures.
Resolve the Reservoir Walker trigger, causing you to gain 3 life and to get {E}{E}{E}.
Repeat.

Infinite death triggers

Infinite sacrifice triggers

Infinite untap of creatures

Audacious Reshapers

Mortuary

Intruder Alarm

Declare Lightning Runner as an attacker, triggering its ability.
Holding priority, activate Circle of Dreams Druid by tapping it, adding at least six {G}.
Activate Emiel by paying {3}, blinking Reservoir Walker.
Reservoir Walker enters the battlefield, causing you to get {E}{E}{E} and gain three life.
Repeat from step 3 one additional time.
Resolve the Lightning Runner ability from step 1, causing you to get {E}{E}, then pay eight {E} to untap all creatures you control, and to get an additional combat phase after this one.
Repeat each combat phase.

Emiel the Blessed

Circle of Dreams Druid

Combos with "Reservoir Walker"