Age of Empires II: Definitive Edition

You can gain this achievement while going through the campaigns.

Continent: Europe
Campaign: Ivaylo
Mission: 2. An Unlikely Alliance

When you start the mission the countdown begins from 200.
Make your way to your allies base and start building your army (you should be around 130-140 years left.
Continue base/army building and when it reaches <100 **<10 years send your army to the highlighted wonder (Church of the Patriarchs)
Once you're next to it you will automatically capture it and will unlock the achievement.

**Important Note:
This achievement currently requires you to be under 10 years remaining to achieve, not <100 as indicated by the achievement description. This is most likely a glitch.

You can do this without unlocking campaign missions or asking a human buddy.

Hop into a single player skirmish and in the "Defend the Wonder" game mode. What might've tricked folks up is the "Player 1" requirement as you cannot move yourself out of the first slot in the list, but "Player 1" isn't about position, it's literally a button next to your name that you can change. Change it so your AI buddy is "Player 1." ;)

The common achievement settings:

2 players
Tiny (2 player)
Easiest AI Difficulty
Infinite Resources
Population 500
Game Speed Fast

I went with Goths, but it really doesn't matter. Spam some Castles, churn out 15 Trebuchets and some unique units. Build some houses. Build some villagers to speed up construction. Do a little damage to keep the enemy's buildings and army in check, but of course wait for 100 years left before doing damage to the Wonder as that building will melt under fire from your trebuchets.

The easiest way to get this is to boost this with 1 partner while going for the


Choose the Chinese as your Civ.

Make sure you start with the default boosting settings:
Infinite Resources
Post Imperial Age as starting Age
Fast gameplay
All Visible
500 max Pop

Turbo on
Full tech tree on / off, no relevance for this achievement

Winning conditions: Standard

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Both you and your opponent / boosting partner should do this and completely mirror each other:

-Build a some Castles and Town Centres and spam build 40-60 villagers and about 120 Chu Ko Nu.
-With your Villagers start building 2 Wonders.
-Select 60 Chu Ko Nu's and press ctrl + 1
-Select the other 60 and press ctrl + 2
-Now put both groups on Stand Ground mode

When the wonder completes, have your opponent attack it with 1 of his groups and repair the Wonder constantly. It takes about 17-18 fully repairs to get the amount of arrows required (If want to keep track of it then I recommend stop and starting the attack and repair rather than doing them simultaneously)

Both of you can now do this for 2 wonders at the same time to speed things up.

your 100.000 arrow achievement will pop mid game so just be patient, this will take 10 min of shooting tops. Plenty of time to wait until the countdown goes beyond a 100 years and for you to kill it

I tried Sky Maniac guide (wait until 10 years on Mission 2 of Ivaylo's campaign) and didn't work for me. Then I read "is that Hydro" comment and it worked. The method I will describe below is to cheese the entire scenario with Bombard Cannon + attack ground combo. This works because every single player will be your ally and the Wonder timer won't start until you convert Alfonso, giving you all the time in the world to boom and then one-shot the Wonder.

Remember: people report you need to be under 10 years to get the achievement (instead of 100 years as the achievement's text says).

Continent: Africa
Campaign: Francisco de Almeida
Mission: 5. "A son's Blood"

Steps list:
0) At any point during the game, pick stone, build a Town Center, and boom.
1) Convert every Alfonso's men, except Alfonso himself and the champion beside him.
2) Build a dock at the north bridge (near Yellow's palisade). Build a Galleon, put it on no attack stance and sail southeast, to the 3 Alfonso's transport ship. Attack the middle one to make it reach the shoreline. Recommended: start trading with Purple's dock (which gives 52 gold per trade).
3) Convert the transport ship while microing the Galleon to prevent it from escaping from Monk's convertion range.
4) Unload the Bombard Cannon and convert it. Quickly put it in no attack stance (so it doesn't aggro Alfonso accidentally). Optional: convert, kill or unload somewhere else the rest of the units inside that transport.
5) Load the Bombard Cannon inside the transport and get it across Green's locked palisade gate.
6) Attack ground every single dock. Optional: if you feel like it, attack ground every military building.
7) Once you feel like you are ready, convert Alfonso. The Wonder timer will start. Inmediatly afterwards, start advancing to Imperial Age.
8) From here, you get to choose how to destroy the Wonder: Rams, Petards, Trebuchets, Bombard Cannons, Cannon Galleons. Mass up whichever you like the most and then one-shot the Wonder once the timer reaches 10 years left.

5th Sundjata mission worked for me.
SAVE OFTEN.

priorities at start of game are:
1) get 3rd TC built at top of map and start churning out villagers. eventually get to 40 villagers or so
2) build a small navy of 10 fast fireships, 10 warships, and 1-2 cannonships. then destroy and patrol the enemy's shore, destroying shipyards and all battle/fish ships. they will rebuild shipyards, so continue to patrol.
3) at the chokepoint, build walls and towers. you'll get some pressure here, but not too much of standard difficulty and your thinning out of the fishing ships.

after that, the game is straightforward. build some castles near their base. defeat orange and thin out red. watch for red to start building their wonder. build up some cannons and gbeto soldiers. once timer hits 100 years, take it down.