Extra Ops/Rare Boss

**Rare Boss Extra Ops** are one of the current Extra Ops type available in *Metal Slug Attack*.

## Overview

Rare Boss Extra Ops are similar to Marathon and Task Force Extra Ops in that they are all single-player Extra Ops. These Extra Ops consist of ten stages, with the first boss at seventh stage. After seventh stage, the difficulty of the enemies ramps up significantly. The first five stages yield medals upon clearing the first time, and the last five give boss parts, enough to unlock the unit.

First three stages contain three P.O.Ws, and the remaining stages have four.

### Rare Boss

After clearing a stage, the Rare Boss has a chance of appearing in which a warning screen will appear and then the stage in which the Rare Boss is located. Typically the Rare Boss is the rare unit accompanying the boss as part of its team bonus, but some of these units have occasionally been replaced if placement problems are an issue. Stages 7 and 10, the boss stages, use the boss, while the rare unit is an enemy reinforcement.

Only one Rare Boss can be present at a time, and only for one hour before despawning. Rare Boss stages yield an additional 50% base points over their normal counterparts. Be on the lookout for Expert Units which raise the Rare Boss appearance rate, which makes obtaining Rare Bosses significantly easier.

There are always four P.O.Ws regardless of the stage the Rare Boss sets in. The side unit is typically of a "Rare" rarity; P.O.Ws always give a part of this unit as a reward. Although exceedingly rare, if the side unit is of a "Super Rare" rarity, then the P.O.Ws may give 100,000 MSP instead. The player has forty-nine (49) rolls for a stage to generate a Rare Boss upon completion or raid; if all of these chances are used and no Rare Boss has yet to appear, the next completed level will yield a Rare Boss. These rolls reset whenever a Rare Boss is generated.

Occasionally there will be a purple P.O.W near the Rare Boss alert, which guarantees a Status Strengthening item. Simply clear the stage the Rare Boss is in to obtain the item.

### Rewards

The rewards table for Rare Boss is modified differently compared to Marathon Extra Ops. The player still obtains "points" from each mission, but due to the decreased sortie usage, the amount of points gained is less, which is also determined by how long the Extra Ops lasts.

The rewards table is also less generous in medals compared to Marathon, offering only 400 medals compared to 800. The player obtains the boss unit at gold frame upon reaching 280,000 points, and a random SR unit's parts are added after 210,000 points. The player still obtains the boss unit at platnium frame at 500,000 points.

It also provides Ultimate Grenade Launchers and Whips, both exclusive to this Extra Ops. The former is an item used to create skill 3 items for Ultimate Bosses, and the latter used for skill 5 items for said units.

## Challenges

Challenges are missions that appears 72 hours before the end of the Extra Ops. There are eighteen missions in total, six in each difficulty, and completing the task will give a reward.

In Glow in the Dark and No Limit, the task was about to make appear the Rare Boss. Then starting Eternal Way, the tasks was changed to clear the stage instead. Rare boss stages cannot be used as a substitute for completing stage-specific challenges - the normal stage has to be completed.

**Note:** The rare boss can be summoned through raiding the stage.