Build guide:

Why cremation ?
Pros:
-CI+melding of the flesh+block+necro ascendancy offers premium defenses at budget making it very comfortable to place towers / enter proximity shields
-scales dmg with 200% increased monsters health unique map mod on ravaged-blight maps
-2 button build
-can do all mods and farm corrupted maps
-while not best in the game, still reliable simu30 farmer
-100div version can kill ubers but not really uber-farmer without conversion to posion(Mirror+ budget)
-30 div budget is enough to farm 10-12div/h strats
-fun build to play

Cons:
-3.23 nerf to no. of geysers took away lots of DPS
-Hexblast is cheaper and possibly stronger under 15 div budget
-DMG sucks early on outside of ravaged maps
-not SSF friendly
-Expensive upgrades(ashes, oriath's end, corrupted uniques, +2 sceptre)


1. Leveling:
DD leveling guide: https://maxroll.gg/poe/build-guides/detonate-dead-elementalist-league-starter-guide
imexile campaign rush ele DD: https://www.youtube.com/watch?v=-OBrBCok4h0
imexile campaign rush necro DD: https://www.youtube.com/watch?v=fw8uLPwvQLU
LHTHC POB: good notes for lvling https://pobb.in/Qi40H0bTE7gC

Two ways for leveling:

A) Necro crema, probably slower campaign (if you aim to clear it under 6h), less rework when transitin into ravaged map farming day2/3(lvl88 recommended), smooth transition into version that clears all mods corrupted maps.

After we finish campaign we don't swap to DD! We just continue playing crema + armageddon brand to make ravaged swap easier. Focus on improving your gear and refer to the excel file with item listings and priority.

B) Elementalist DD, need to swap from campaign crema to dd then swap again to necro/cremation later.
Last league footage (+good tips in comments): https://www.youtube.com/watch?v=C8LjqrVTQEM

2. Swap to Cremation/Necro (15div)
So regardless of your leveling strat, your ravaged-blight build is ready at level 87, or earlier if you get more currency for 6L and stuff.
Auto chest opening is premium with 5L, i'd rather do that manually over losing golden+silver oils, so it's in the POB but offered at level 91.

This is the point of build power where it should be 100% win ratio unless you do something wrong, which is fine if you're just learning how to farm ravaged maps.

Poorman's Cremation 5L POB: https://pobb.in/mUb7_XSIttJq

3. 6L + Oriath's end(30div budget):

This upgrade trivializes the content
Real POB 3.23: https://pobb.in/MNtwyJWNzFO1

4. Final upgrade, 2 cluster jewels, ashes, +2 weapon etc. (100div)

POB: https://pobb.in/r_V-mkTEHPWz




Strategy explained:
1. Clear few maps to find cassia which is now required to anoint your maps and rings.

2. If you can't afford maps, do unidentified chaos recipe (2c for set of all items). There are some tools to help you out with that but myself I don't bother.

3. Ring anoints:
Teal + Violet (Scout tower Range)
Amber + Amber (Scout tower DMG)

For non-amber red blighted maps:
Indigo + Violet (Meteor tower burning grounds)
Opal + Silver (Chilling tower freeze)

For Ravaged maps:
Opal + Silver (Chilling towers freeze) AND
a) Verdant + Black (Empowering towers range) OR
b) Golden + Violet (imbuing towers increase dmg by 50%) OR
c) Opal + Opal (Smothering towers decrease movement speed by 20%) OR
d) Teal + Teal (Smothering towers increased effect by 25% )

4. Early blighted maps:

Oils:
Amber+Amber+
1: Clear/Sephia - first maps only for extra safety
2. Azure - If you don't have crimsons/black
3. Crimson/Black - don't buy them, use what you dropped

Map tiers:
Early on your goal is to build positive currency flow to be able to afford next runs. Not losing is more important than oils and map tier, so make sure you run maps you can clear so you don't waste time and chaos orbs.

First map suggested:

No amber oils - t1-t2
2x amber oils - t3-t6

Later farm yellow maps (according to your level)

Red Blighted maps:
It's worth to run red maps with 2x amber, but i'd rather farm t12 with non-amber oils rather than clearing t15 with 2x amber. Leveling up makes the content easier and lets you clear higher tiers without much eq changes. Successful map = deathless run  and completed encounter.

Oils:

First red maps:
Amber+Amber+Crimson/black
Red blighted maps day1 strategy guide: https://www.youtube.com/watch?v=H4g9TPgmKsQ

More currency strat:
3x crimson - focus on wealth building, good early as you sustain crimson oils with violet upgrades, replace with black/opal at will if you have them

More XP strat:
3x teal, fast clears, cheap, fully sustainable, more XP. I'd recommend that if you want to rush ravaged maps as lvl > 86 is crucial to farm the content more comfortable

Ravaged map strategy:

1h Gameplay with lvl88: https://www.youtube.com/watch?v=9BujcedWfYM

Playstyle:

Build crossroads of chilling (lvl3 frost), stun (lvl3) and empower (lvl3), glacial tower near the pump, imbuing tower near the pump/or when needing extra DPS, smothering towers

So early on, there's very little difference between non-golden oil strategies and 3x crimson blighted maps. Thus it's not that huge difference day1 vs farming normal blighted maps with CCC.

Based on supply and economy few strategies are worth concerning:

1. Strong supply of oils / maps good economy - GSSSOOTTT
2. Low supply of oils / maps - GSSSOOOBB*
3. Low supply of oils but good supply of maps - CCCBBBTTT*

* - I have not measured and compared different starting strategies in league start economy condition so it's a preference and probably comes down to price/supply of expesnive oils and price of the map. It's definitely not going to be as profitable as GSSSOOTTT if you could run 10 maps/hour so more like preference of TTT vs non teal.

Last league day3 profits were 15div/h(+profit from jewellery, bases and flasks), it was quite hard to buy maps and oils in bulk, but profits from alter orbs and bubble gum currency were crazy good (compared to price of MB or Mirror). Unfortunately later days oils went up by a lot while bubble gum got cheaper and profits went down to 7/8 div/h, this is why its important to use the momentum for your own advantage and buy stuff that goes up in price quickly (MB/HH/Mirror cards etc.)


Oils day3-7:

GSSSOOTTT - When you have enough map/oil supply to run it. Teal makes it easier as you have always spot to build stunlock crossroad (freeze+stun+empower)

GSSSOOOBBB - Less div/h but more loot/map. Makes it easier to sustain wealth and if you don't have enough oils/maps to run it in 5/10 map sessions one after another. Might be hard if you have poor defenses and you'll end up in t16 layout with just 3 tower slots in first 2 minutes (happened to me once).

Oils days7-21:

GGSSSOTTT - only if you can sustain oils, probably similar profits to single golden oil but you increase chances for big drops so if you can afford, why not.

Corrupt ravaged maps only if tainted oil cost is reasonable. If it's 20c its actually less profitable because you get random rarity and quantity and the average is less than if we juice all our non-corrupted maps to 40%+ rarity.

Twist of fate/unid rework might change this, but I need to test it.