Haakon, Stromgald Scourge +
Phyrexian Altar + 7 sackable creatures +
Elenda, the Dusk Rose in the graveyard: Infinite tokens, mana, and an infinitely large Elenda. Sacing 4 creatures for mana to cast Elenda from the grave, sac the 3 remaining tokens(buffing Elenda, adding mana) then Elenda, get 4 tokens, cast Elenda again. Repeat, gaining an extra token each time.
Animation Module + Elenda, the Dusk Rose + one creature + Phyrexian Altar/Ashnod's Altar: An infinitely large Elenda and infinite colorless mana with Ashnod's. Sacking a creature puts a counter on Elenda, pay for the Module, which gives you another creature to sac. This can be done with another creature, substituting for Elenda with Cordial Vampire.
Nim Deathmantle + Elenda, the Dusk Rose(unbuffed) + Ashnod's Altar: Infinite tokens, infinitely big Elenda. Sac Elenda for 2 mana, stack the death triggers so you get the Vampire token first, sac the token 2 mana to pay for Deathmantle to catch Elenda. This brings Elenda back with Deathmantle attached, which givers her +2/+2, so you can continue the loop.
For the above combo, Elenda can be replaced by any creature like Chittering Witch or Ministrant of Obligation for infinite tokens.
Elenda, the Dusk Rose(unbuffed) + Nim Deathmantle + Phyrexian Altar + 2 other creatures: Infinite tokens and infinitely big Elenda. Same concept as above, just requires more set-up. You have to sac two extra creatures when Elenda is on the field so you get extra Vampire Tokens. Much easier and immediately infinite if Elenda is a 4/4 or bigger.
Elenda, the Dusk Rose(unbuffed) + 1 creature + Teysa Karlov + Phyrexian Altar = Infinite Tokens, and infinitly big Elenda, and infinite colored mana. This works due to the new ruling allowing you to re-zone Elenda even when she dies. This combo also comes at the cost of infinite commander tax. Sac the extra creature, then Elenda, Teysa doubles the counters and tokens produced, allowing you to sac the tokens for more mana and recast Elenda, and repeat.
Nightmare Shepherd + Phyrexian Altar + Elenda, the Dusk Rose(as a 3/3): Infinite tokens, infinitely big Elenda, and infinite colored mana. Elenda has to have 3 power or more, and can't have a commander tax (if she does, you just need that much more mana). A combo of my own invention, and it's super confusing. Here's how it works.
- Using Phyrexian Altar to sac and add mana, sac Elenda, get 3 tokens.
- Shepherd exiles Elenda from the yard, creating a copy of Elenda (ElendaCopy). Send Elenda to the command zone.
- Sac 3 tokens (4 mana now), buff ElendaCopy (4/4), sac ElendaCopy, get 4 tokens (and now 5 mana total).
- Sac a token, use the 6 mana to cast Elenda from the command zone. Elenda is 1/1 and we have 3 tokens.
- Sac three tokens, buff Elenda (4/4, 3 mana).
- Sac Elenda, send her to command zone, make ElendaCopy and 4 tokens (we have 4 mana).
- Sac 4 tokens, 8 mana, ElendaCopy is 5/5.
- Cast Elenda with 8 mana. sac Elenda copy to the Legend rule, Elenda is 2/2 and we have 5 tokens.
Understanding the loop: Take note of the two bold sentences. At both points we have just cast Elenda from the command Zone, and we have 0 mana. The important thing to note is we are up 3 resources (tokens and/or power on Elenda, both of which convert into mana via the Altar) in the second bold sentence, meaning we've gone positive over the 2 mana commander tax each loop. If we continue this loop, the next time we're in this position, Elenda is a 2/2, and we have 8 tokens and 3 mana (up 6 resources from previous stopping point). Thus, infinite colored mana and tokens, and an infinitely big Elenda. Risky because if we get blown up, Elenda's commander tax is infinite.
Sun Titan + Gift of Immortality + Sac outlet: Infite ETB/death triggers. Can be combined with Elenda and other pieces for infinite mana, creature destruction, draw, +1/+1 counters, tokens, etc.
Animation Module + Cathars' Crusade + Ashnod's Altar + A few creatures and/or some mana: Infinite big infinite tokens. Play a creature, it gets a +1/+1 counter, pay 1 to create a servo, they all get counters, pay for as much as you can, using the Altar to go positive on mana and tokens each time.
Gift of Immortality + Elenda, the Dusk Rose + Sac outlet: Not exactly infinite, but you can sac Elenda each turn to gain a token.
ON THE SIDEBOARD
Combos and cards I've tested and like, and might go back to someday:
Decaying Soil(with threshold) + Deathrender + Phyrexian Altar/Ashnod's Altar: Infinite ETB/LBF triggers. Sac the creature, Deathrender triggers first and Decaying Soil resolves first, puting the creature you sacked back into your hand for deathrender. This can be combined with many of my creatures for infinite mana, tokens, or +1/+1s.
Deathrender + Together Forever + Elenda, the Dusk Rose + Altar: Infinite tokens and ETBs. This one is tricky to set up. To start, you need a counter on Elenda(which isn't too hard) and Deathrender equipped to her. Sac Elenda to get one or two mana depending on the Altar, stack the Together Forever trigger over the Deathrender trigger, use the mana to pay 1 so Elenda returns to your hand, put her onto the battlefield with Deathrender. Repeat for infinite tokens and mana.
The Deathrender + Together Forever + Altar can be achieved with any other creature and Cathars' Crusade for infinite ETB/LBFs. It can also work with Unspeakable Symbol but the life loss prevents it from becoming infinite.
Deathrender + Razaketh, the Foulblooded + one creature to sac + one creature in hand: Not exactly infinite, but at the cost of 2 life I can cycle through all the creatures in my deck until victory is achieved by any number of different ways.
With Haakon out, you could cast Nameless Inversion as many times as you have mana. Trying to find room for Crib Swap to do the same thing.