Zinnia, Valley's Voice, Appa, Steadfast Guardian, Priest of Urabrask, and Adrix and Nev, Twincasters

Prerequisites

• Zinnia, Valley's Voice on the battlefield
• Appa, Steadfast Guardian in hand
• Priest of Urabrask in hand
• Adrix and Nev, Twincasters on the battlefield
• available

Steps

1. Cast Priest of Urabrask by paying its mana cost plus an additional for its offspring cost
2. When Priest of Urabrask enters, its innate ability and its offspring ability trigger
3. Resolve the innate Priest of Urabrask trigger, adding Resolve the offspring trigger, creating two token copies of Priest of Urabrask that are 1/1
4. When the Priest of Urabrask tokens enter, they each trigger, adding six
5. Cast Appa by paying its mana cost plus an additional for its offspring cost
6. When Appa enters, its innate ability and its offspring ability trigger
7. Resolve the innate Appa trigger, airbending the nontoken Priest of Urabrask
8. Resolve the offspring trigger, creating two token copies of Appa that are 1/1
9. Put both Appa tokens into your graveyard due to the legend rule
10. Both Appa tokens' enter-the-battlefield ability trigger, airbending Appa with one trigger and nothing with the other
11. Cast Priest of Urabrask from exile by paying plus an additional for its offspring cost
12. Repeat steps 2 through 5 once
13. Cast Appa from exile by paying plus an additional for its offspring cost
14. Repeat from step 7

Results

• Infinite ETB
• Infinite LTB
• Infinite blinking of nonland permanents
• Infinite creature tokens
• Infinite red mana
• Infinite storm count