Survey Mechan + Mortuary + Ashnod's Altar + Insidious Roots + Exalted Sunborn

Survey Mechan

Mortuary

Ashnod's Altar

Insidious Roots

Exalted Sunborn

How it works

1. Activate Survey Mechan by sacrificing it.
2. When Survey Mechan dies, Mortuary triggers, putting Survey Mechan from your graveyard onto the top of your library.
3. Insidious Roots triggers, creating two creature tokens and putting a +1/+1 counter on each Plant you control.
4. Resolve the Survey Mechan ability, dealing 3 damage to any target and causing you to draw three cards and gain 3 life.
5. Activate Ashnod's Altar twice by sacrificing the two creature tokens, adding CCCC.
6. Cast Survey Mechan by paying 4.
7. Repeat.

This loop transforms the high mana cost of Survey Mechan into an engine of endless rebirth by using Ashnod's Altar to sacrifice the tokens generated along the way. Whenever Survey Mechan hits your graveyard, Mortuary neatly tucks it back onto the top of your library so you can draw it right back, while Insidious Roots watches those creature cards leave your graveyard to flood the board with Plant tokens. The real magic happens with Exalted Sunborn, whose static replacement effect doubles every single token created, ensuring that Insidious Roots produces twice as many bodies to feed into Ashnod's Altar for more than enough mana to cast Survey Mechan again.