Combos with Dack's Duplicate

1. Activate Kiki-Jiki by tapping it, creating a token copy of Dack's Duplicate that has haste. Choose to have Dack's Duplicate enter as a copy of Kiki-Jiki.
2. Put the oldest Kiki-Jiki into the graveyard due to the legend rule.
3. Repeat step 1 using the Dack's Duplicate token instead.

1. Cast Dack's Duplicate by paying its mana cost, choosing to have it enter the battlefield as a copy of Felidar Guardian
2. When Dack's Duplicate enters the battlefield, it triggers, blinking Felidar Guardian.
3. When Felidar Guardian enters the battlefield, it triggers, blinking Dack's Duplicate. Choose to have Dack's Duplicate enter the battlefield as a copy of Felidar Guardian.
4. Repeat from step 2.

1. Cast Dack's Duplicate by paying its mana cost, choosing to have it enter the battlefield as a copy of Wispweaver Angel
2. When Dack's Duplicate enters the battlefield, it triggers, blinking Wispweaver Angel.
3. When Wispweaver Angel enters the battlefield, it triggers, blinking Dack's Duplicate. Choose to have Dack's Duplicate enter the battlefield as a copy of Wispweaver Angel.
4. Repeat from step 2.

1. Cast Dack's Duplicate by paying its mana cost, choosing to have it enter the battlefield as a copy of Bladewing.
2. Put Bladewing into your graveyard due to the legend rule.
3. Dack's Duplicate's enter-the-battlefield ability triggers, returning Bladewing from your graveyard to the battlefield.
4. Put Bladewing into your graveyard due to the legend rule.
5. Bladewing's enter-the-battlefield ability triggers, returning it from your graveyard to the battlefield.
6. Repeat from step 4.

Activate Dack's Duplicate by paying {1}{U}, shuffling Dack's Duplicate into your library and milling your entire library due to it not having a card named Mirror-Mad Phantasm in it.

1. Activate Kiora's Follower by tapping it, targeting Dack's Duplicate.
2. Illusionist's Bracers triggers, copying Kiora's Follower's ability.
3. Resolve both Kiora's Follower abilities, untapping Dack's Duplicate and another permanent you control.
4. Activate Dack's Duplicate by tapping it, untapping Kiora's Follower.
5. Repeat.

1. Cast Dack's Duplicate by paying its mana cost. Choose to have it enter as a copy of Anticausal Vestige.
2. When Dack's Duplicate enters, Cloudstone Curio triggers, returning Anticausal Vestige from the battlefield to your hand.
3. When Anticausal Vestige leaves the battlefield, it triggers, causing you to draw a card and and put Anticausal Vestige from your hand onto the battlefield.
4. When Anticausal Vestige enters, Cloudstone Curio triggers, returning Dack's Duplicate from the battlefield to your hand.
5. When Dack's Duplicate leaves the battlefield, it triggers, causing you to draw a card and put Dack's Duplicate from your hand onto the battlefield as a copy of Anticausal Vestige.
6. Repeat from step 2.

1. Cast Dack's Duplicate by paying its mana cost, choosing to have it enter the battlefield as a copy of Abdel Adrian.
2. Put the original Abdel Adrian into your graveyard due to the legend rule, causing Karmic Guide to return to the battlefield from exile.
3. Karmic Guide and Dack's Duplicate's abilities trigger.
4. Resolve the Dack's Duplicate ability, choosing to exile Karmic Guide until Dack's Duplicate leaves the battlefield and creating a 1/1 Soldier creature token.
5. Resolve the Karmic Guide trigger, returning Abdel Adrian from your graveyard to the battlefield.
6. Put Dack's Duplicate into your graveyard due to the legend rule, causing Karmic Guide to return to the battlefield from exile.
7. Karmic Guide and Abdel Adrian's abilities trigger.
8. Resolve the Abdel Adrian ability, exiling Karmic Guide until Abdel Adrian leaves the battlefield and creating a 1/1 Soldier creature token.
9. Resolve the Karmic Guide trigger, returning Dack's Duplicate from your graveyard to the battlefield as a copy of Abdel Adrian.
10. Repeat from step 2.

1. Cast Dack's Duplicate by paying its mana cost. Choose to have it enter the battlefield as a copy of Rakdos Joins Up.
2. Put Dack's Duplicate into your graveyard due to the legend rule.
3. Dack's Duplicate's first ability and second ability trigger, along with Rakdos Joins Up's second ability.
4. Resolve Dack's Duplicate's second trigger and Rakdos Joins Up's trigger, dealing damage to target opponent.
5. Resolve Dack's Duplicate's first trigger, returning it from your graveyard to the battlefield with two +1/+1 counters on it as a copy of Rakdos Joins Up.
6. Repeat from step 2.

1. Activate Zur by paying {1}{W}, causing Rakdos Joins Up to become a creature.
2. Cast Dack's Duplicate by paying its mana cost. Choose to have it enter the battlefield as a copy of Rakdos Joins Up.
3. Put Dack's Duplicate into your graveyard due to the legend rule.
4. Dack's Duplicate's first ability and second ability trigger, along with Rakdos Joins Up's second ability.
5. Resolve Dack's Duplicate's second trigger and Rakdos Joins Up's trigger, dealing damage to target opponent and causing you to gain that much life.
6. Resolve Dack's Duplicate's first trigger, returning it from your graveyard to the battlefield with two +1/+1 counters on it as a copy of Rakdos Joins Up.
7. Repeat from step 3.

1. Cast Dack's Duplicate by paying its mana cost. Choose to have it enter as a copy of Honest Rutstein.
2. Put Honest Rutstein into your graveyard due to the legend rule.
3. Dack's Duplicate triggers, returning Honest Rutstein from your graveyard to your hand.
4. Cast Honest Rutstein by paying {0} due to Morophon and Dack's Duplicate.
5. Put Honest Rutstein into your graveyard due to the legend rule.
6. Honest Rutstein triggers, returning it from your graveyard to your hand.
7. Repeat from step 4.

1. Cast Dack's Duplicate by paying its mana cost. Choose to have it enter as a copy of Princess Yue.
2. Put Dack's Duplicate into your graveyard due to the legend rule.
3. When Dack's Duplicate dies, it triggers, returning it from your graveyard to the battlefield as a land named Moon. Choose to have it enter as a copy of Astral Dragon, gaining its abilities.
4. When Dack's Duplicate enters, it triggers, creating two token copies of itself, thus creating two copies of Moon with Astral Dragon's abilities, that are 3/3 Dragon creatures in addition to its other types.
5. Put all but one of the [[clones]] into your graveyard due to the legend rule.
6. The Dack's Duplicate tokens each trigger. Resolve a trigger, creating two token copies of itself, thus creating two copies of Moon with Astral Dragon's abilities, that are 3/3 Dragon creatures in addition to its other types.
7. Repeat from step 5.

1. Cast Dack's Duplicate by paying its mana cost. Choose to have it enter as a copy of Princess Yue.
2. Put Dack's Duplicate into your graveyard due to the legend rule.
3. When Dack's Duplicate dies, it triggers, returning it from your graveyard to the battlefield as a land named Moon. Choose to have it enter as a copy of Wormfang Turtle, gaining its abilities.
4. When Dack's Duplicate enters, its first ability triggers, exiling it.
5. When Dack's Duplicate leaves the battlefield, its second ability triggers, returning Dack's Duplicate from exile to the battlefield. Choose to have it enter as a copy of Princess Yue.
6. Repeat from step 2.

1. Cast Dack's Duplicate by paying its mana cost. Choose to have it enter as a copy of Princess Yue.
2. Put Dack's Duplicate into your graveyard due to the legend rule.
3. When Dack's Duplicate dies, it triggers, returning it from your graveyard to the battlefield as a land named Moon. Choose to have it enter as a copy of Wormfang Newt, gaining its abilities.
4. When Dack's Duplicate enters, its first ability triggers, exiling it.
5. When Dack's Duplicate leaves the battlefield, its second ability triggers, returning Dack's Duplicate from exile to the battlefield. Choose to have it enter as a copy of Princess Yue.
6. Repeat from step 2.

1. Activate Forensic Researcher by tapping it, targeting Dack's Duplicate.
2. Deeproot Pilgrimage triggers, creating a 1/1 Merfolk creature token.
3. Resolve the Forensic Researcher ability, untapping Dack's Duplicate.
4. Activate Dack's Duplicate by tapping it, targeting Forensic Researcher.
5. Deeproot Pilgrimage triggers, creating a 1/1 Merfolk creature token.
6. Resolve the Dack's Duplicate ability, untapping Forensic Researcher.
7. Repeat.