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How To Use This Page Read First

Each research tree below has a visual reference and ECHO's recommended priority. Click a tree card to see the full-size image and expanded doctrine notes.

Golden rule: match your research investment to your account phase. Early accounts benefit exponentially from Economy research. Mid-game accounts need Combat multipliers. Season-specific research (Bio Lab, seasonal buffs) always takes priority when a season is active.

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Core Research Trees

Combat Research Tree
Combat Tree
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Combat

HIGH PRIORITY

Attack, defense, and health multipliers for your troops. The single highest-impact research tree for any account past mid-game — these percentages compound on every troop you train.

ECHO doctrine: Push this hard once you have Tier 4 troops. Every level here makes your entire army stronger, so it pays back faster than nearly any other investment.

Economy Research Tree
Economy Tree
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Economy

EARLY PRIORITY

Resource production multipliers, gathering speed, march load. Pays for itself within days at low levels — this is where new accounts should invest first.

ECHO doctrine: First tree to push in Phase 1-2 (days 1-30). Higher production means faster upgrades everywhere else. Don't skip.

Defense Research Tree
Defense Tree
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Defense

MEDIUM PRIORITY

Wall HP, garrison bonuses, trap damage, and city defense multipliers. Reduces losses when you're attacked and improves counter-rally value.

ECHO doctrine: Push after Combat is healthy. Discipline (shielding when told) matters more than raw defensive stats — but every level here reduces losses when a shield fails or a raid slips through.

Growth Research Tree
Growth Tree
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Growth & March

HIGH PRIORITY

March capacity, build speed, training speed, and healing speed. Compounding infrastructure gains that pay back for the entire life of the account.

ECHO doctrine: March capacity nodes are top-tier — bigger marches gather more, hit harder, and reinforce faster. Prioritize these alongside Economy in Phase 2.

Hero Research Tree
Hero Tree
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Hero

MEDIUM PRIORITY

Unlocks hero slots, reduces cooldowns, boosts skill levels, and increases hero attack/health caps. Multiplies the value of your invested hero fragments.

ECHO doctrine: Push this in parallel with your S-tier hero upgrades. A maxed hero with no research support underperforms — the tree makes your fragments count.

Season Research Tree
Season Tree
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Season / Special

CRITICAL WHEN ACTIVE

Season-specific research that unlocks with each new season (Bio Lab in S2, etc.). Provides resistance, seasonal creature damage, and event scaling. Resets or transforms between seasons.

ECHO doctrine: When a season is active, this always takes priority over evergreen trees. Falling behind on seasonal research locks you out of better creature access and event scoring. See the Season 2 page for current-season specifics.

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Recommended Investment Order

ECHO's default research investment order for a growing account:

  1. Season / Special — whenever a season is live, this comes first
  2. Economy — early game (Phase 1-2), compounds fastest
  3. Growth & March — parallel with Economy, especially March Capacity nodes
  4. Combat — once you hit Tier 4 troops, push aggressively
  5. Hero — in parallel with hero fragment investments
  6. Defense — after the offensive base is healthy

Do not spread your research points thinly across every tree. Depth beats breadth. Finishing a tier of a high-priority tree is worth more than starting three trees at level 1.

Want To Plan Your Own Research? Tool

The community-built Last Z Helper research tree planner lets you click through every node, mark them complete, and track badge costs. Save your progress and see exactly how much you've invested versus what's still ahead.

External site — not affiliated with ECHO or the game developer. See Community Tools for other resources.

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