Rockfield & You

This guide explains why the all-planes Rockfield march works, when to use it, and what actually affects its damage. TL;DR: you MUST send a full Air Force march, and the only things that change Rockfield’s opening hit are unit level average and march size difference.

Click here to visit the rockfield calculator!

Credit to tzup and Bobgrif, who provided most of the text for this guide.

MOST IMPORTANTLY: You MUST Use All Planes

If you put any other troop type in the march, it will not work.
For small players, this can chip away at a mega-whale sitting in a building when you otherwise wouldn’t kill a single troop.
Useful for defense as a Battle Round–filling march to help chip whales hitting the building so your bigs stand a better chance when the heavy hits land.
The mechanics: Rockfield performs a single attack that occurs after start-of-round buffs and before any Hero or HT triggers based on Attack Speed or High Rate of Fire.

Key to Taking More Troops (for higher-level players)

The more troops the opponent has compared to you, the less effective Rockfield’s hit becomes. If the opponent uses higher troop level (e.g., 101 vs 103), Rockfield’s effectiveness is reduced. For most players, the goal is a small suicide march that removes ~5–10 units per stack and slightly lowers the whale’s stack size so others can knock them out.

FAQ for Rockfield March

Do we have to send a full march?
Yes. Full march. Avoid HT if you’re using Valhallas or 102 units since HT is level 101. Unit level average is most important. Valhallas do best; 101/102 are fine.
Do we have to send only planes?
Yes. The march must be all planes or it will not work at all. Rockfield’s skill requires a full Air Force march.
Do the other two heroes matter?
Not for the Rockfield hit itself. Ideally pick heroes that maximize march size (bigger march reduces the penalty). You can add 100% trigger-rate heroes to try for extra damage, but march size matters more.

Why This Works

Rockfield’s skill executes a single massive blow at the start of the fight. It cannot be stopped, silenced, stunned, or mitigated in any way. It happens once, and only once.

The damage is based on a percentage of each enemy stack’s maximum HP (practically, it translates to a percentage of the full stack being instantly killed). Example: at 27%, a stack of 100 would instantly lose 27 units—assuming perfect conditions.

What Affects the Damage?

Only two things affect Rockfield’s opening hit:

Your Unit Level Average vs Enemy Unit Level
This has the biggest impact.
- 102 vs 103 (Valk) → damage is cut in half (e.g., 27% → 13.5% → ~13 units from a 100 stack).
- 101 vs 103 → cut in half, then in half again (27% → 13.5% → 6.75%). This is why you can still deal some damage 101 vs Valhallas.

Your March Size vs Enemy March Size
Apply a percent penalty based on how much smaller your march is, calculated after the unit-level adjustment.

Scenario	Step	Result
Base %	Base Rockfield %	27%
Level Penalty	102 vs 103	27% → 13.5%
March Size Penalty	300 vs 400 (−25%)	13.5% × (1 − 0.25) = 10.125% (~10.1 units from 100)

These are the only two modifiers that make or break the Rockfield suicide march. Any additional heroes only contribute their own normal damage.

Hero Ideas (independent of Rockfield’s blow)

Maximo – High trigger on middle row; a bit outdated damage-wise now.
Rei Ayanami ES 5+ – Rage hero (starts with 7 rage); first stack will always trigger; damage is modest but guaranteed.
Mega / Gipsy / Po – Strong attack boosters and bomber skills; high damage when triggered.
Any high trigger-rate, high-damage air hero.
Any hero that works on Air.

Again, these do not boost Rockfield’s opening hit; they can only add their own damage after it.

Quick Tips

Send full planes or the march won’t work.
Prioritize unit level average and march size to maximize the opening hit.
Great as a low-count suicide march to peel 5–10 units per stack off whales in buildings.
Useful for defense Battle Round filler to soften incoming whale hits.