Last Z Zombie Siege Strategy Guide for Alliance Leaders

For alliance leaders who keep stalling in Zombie Siege at wave 18 because half the roster burned at wave 10 with no defense squad set.

Zombie Siege is the weekly PvE event in Last Z that shows how prepared your alliance really is. 30 waves of zombies attack every base in the alliance for up to 1 hour 45 minutes. Two failed defenses and your base is out. Wrench rewards scale with how deep the alliance pushes together, not with how strong one base is. This is a coordination event with rewards attached, not an endurance test for your strongest accounts.

Most alliances that stall mid-waves stall for the same three reasons: members who never set a defense squad, leaders who reinforce too early and steal personal points, and rosters that pull troops out for boomers or mining right before the event opens. None of those are skill problems. They are R4 and R5 management problems.

This guide covers what Zombie Siege actually rewards, what your alliance has to lock in before the start timer, and the reinforcement discipline that separates alliances clearing 30 waves from ones knocked out at 18.

The basics every alliance leader needs locked in

Before any tactics, the rules. Get any of these wrong and your roster underperforms, however strong the top players are.

Schedule and duration

Only R4 or R5 officers can schedule Zombie Siege, and only for Monday or Tuesday. Most top alliances run it on Monday, because Wrenches are one of the main rewards and they feed directly into Alliance Duel scoring later in the week. Tuesday squeezes that Wrench to Duel window.

• Duration: 1 hour 45 minutes, or less if every alliance base is wiped out.
• Waves: 30 in total. Each wave attacks every eligible base in the alliance.
• Knockout rule: two failed defenses and your base is out. You stop adding waves to the alliance count.
• Rewards: personal rewards arrive after all members finish. Alliance rewards land on Wednesday after reset.

Always confirm the exact slot in Event Center on Apocalypse Time (server time). If members plan on local time, half your roster will miss the start. Bases without troops home at wave 1 are dead at wave 1.

Why this is an alliance event, not a personal one

Wrench rewards are built around collective wave depth. The further the alliance pushes together, the higher every member's reward tier climbs. One strong account clearing 30 waves alone while half the alliance dies at wave 8 gives a worse result than a coordinated alliance grinding to wave 25 with the bottom half barely alive.

So the R5's real question is not "how do I clear 30 waves on my account". It is "how do I keep my bottom 15 members alive long enough to push the alliance wave count". Resource planning, reinforcement timing and pre-event briefings should all follow from that.

The pre-event checklist (run it every Sunday night)

Zombie Siege is won and lost on Sunday night, not during the event. An R4 and R5 team that runs a tight checklist beats the alliance that figures it out at minute zero.

1. Every member has a defense squad set on their wall. This is the biggest source of avoidable knockouts. A base with no defense squad dies in wave 1, however strong the account. As R5, make it mandatory, pin a reminder and check by screenshot in alliance chat. Do not assume.
2. All troops are home before the event opens. No boomers, no zombie hunting, no mining, no digging treasure, no gathering anywhere on the map. Anyone who sends troops out in the hour before Zombie Siege is gambling on getting them home in time.
3. The strongest formation is on the wall, not deployed. Some members send their best heroes out to gather or hunt by habit. That habit kills them in Zombie Siege. The strongest formation belongs on the wall at full strength. Secondary formations stay free to reinforce weaker members in mid to late waves.
4. Base defenses, research and gear are kept up. Wall durability, turrets and trap upgrades absorb damage before it reaches your squads. Members who skipped base defense because "the wall does not matter for PvP" pay for it here. The same goes for Hero Power and Troop Resistance research nodes, which decide how deep each base gets before the second failure.
5. Reinforcement pairs are assigned in advance. Find your 10 to 15 weakest members ahead of time and assign stronger members to cover them. Do not decide mid-event, because by then it is too late. Publish a reinforcement map on Sunday, for example "Member A and Member B reinforce Member X from wave 18".

The reinforcement rule most alliances get backwards

The most expensive Zombie Siege mistake is reinforcing too early. Sending your top formation to cover a member at wave 4 steals their personal points and adds almost nothing to alliance survival, because the early waves are easy to handle alone.

• Waves 1 to 15: no reinforcements. Members defend their own base and get their personal points undisturbed.
• Waves 16 to 25: reinforcements start. Stronger members cover the weak bases you picked in advance. This is where alliance wave depth gets built.
• Waves 26 to 30: maximum pressure. Anyone still alive sends troops to keep the bottom half of the roster on the board as long as possible.

Reinforcing means committing your own troops one way. Too early and you steal points. Too late and the weak members are already out. The discipline cuts both ways.

Do not burn diamonds putting out burning HQs

Around wave 20 the temptation hits: a member's HQ catches fire, they panic, and they spend 50 diamonds to put it out and stay in. Do not do this, and do not let your members do it.

Every base burns eventually. That is how Zombie Siege is built. 50 diamonds per extinguish, across every member who panics, adds up to a real share of the alliance's diamonds over a season, for a few extra waves and no strategic value. Those diamonds do more in healing, hero packs or research speed-ups that compound across cycles.

Message to post in alliance chat before every Zombie Siege: "Do not extinguish burning HQs with diamonds. Accept the burn and reinforce others until the event ends."

What to do after your base burns

Once your base is out, you stop getting zombie attacks, but you can still help the alliance push wave depth. Send your remaining troops to reinforce weaker members who are still alive. Call it in voice or alliance chat, for example "Member X is at wave 22 with one defense left, sending reinforcements", so support lands where it matters most.

The members who keep playing after their own knockout are the ones who push the alliance from wave 22 to 28. The members who close the app the minute they burn are the ones whose alliances stall.

The priority order for alliance leaders

Every R5 has the same 1 hour 45 minutes. Top alliances run a fixed order:

1. Defense squad compliance. Checked before the event opens. No exceptions.
2. Troops home and strongest formation on the wall. Confirmed in chat by every member.
3. Personal points in waves 1 to 15. No reinforcing, no diamond spending, no panic.
4. Reinforcement in waves 16 to 30. Pre-assigned pairs start. Burned members keep helping.
5. Wrenches collected and lined up for Alliance Duel. Run Zombie Siege on Monday so the Wrenches are ready when Duel scoring starts.

The rule that separates winning alliances from losing ones: Zombie Siege is not about being strong, it is about being prepared together. One unprepared member at wave 1 hurts the alliance more than your strongest account helps at wave 25.

The quick version

• It is a coordination event, not an endurance test. The alliance pushes wave depth together.
• Run it on Monday. Wrenches feed Alliance Duel later in the week. Tuesday squeezes that window.
• Defense squads are not optional. Pin the reminder and check by screenshot. Bases without squads die at wave 1.
• No reinforcing in waves 1 to 15. Early reinforcing steals personal points. Save your top formation for when the alliance needs it.
• Do not extinguish burning HQs. 50 diamonds per extinguish is wasted. Accept the burn, then reinforce others.

Zombie Siege Wrenches feed Alliance Duel, Alliance Duel feeds ranking rewards, and ranking rewards feed the next cycle. That weekly loop only compounds if your roster is ready every week. The wrench guide covers the other Wrench sources.

Win Zombie Siege by treating it as a roster event, not a combat event. The alliance with the best-prepared bottom 15 wins, every time.

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