Metal Slug Defense (Japanese Name :メタルスラッグディフェンス - Metaru Suraggu Difensu) is a tower defense game created by SNK Playmore for iOS and Android mobile devices. It was also ported to Steam.
The latest version of this game is 1.46.0 Ver and has not been updating since 24 April 2016.
Several years after General Morden's coup d'état attempt was defeated... The scattered remains of the Rebel Army have become organized again.
Military intelligence finds that General Morden is alive, and planning another coup d'état.
The Rebel Army and aliens are revealed as behind the mysterious phenomenon happening around the world.
To stop the rebels and aliens from reaching their goals, military intelligence musters troops and dispatches them around the world.
General Morden and the aliens' lust for power pushed the world to the brink of destruction and chaos, only to be stopped at the last moment by the military.
But this does not mean that peace is at hand.
General Morden's death remains unconfirmed...
Could he have survived yet again?
If so, when and how will he attempt this next coup d'état?
And the aliens, as well...
The heroes struggle will not end. So long as there is a battle to be won on our world, they will be there.
The gameplay is a one vs one tower defense/strategy game, with two "sites" on either side of the stage where units are spawned. The main objective of the game is to destroy the opposing site by any means.
Once the game begins, forces begin accruing "AP ", which is used to produce units that automatically advance toward the enemy's site. These units can either assault enemies, construct objects that impede enemies or support allied units, or produce additional units at no cost. Paying Rumi Aikawa a certain amount of will improve the rate that builds as well as the maximum that can be held at once.
Most units have both a standard attack and a special attack. When the unit is within range of an enemy unit or structure, it will begin its standard attack. After a predetermined length of time, the unit's special attack will be available, indicated by a light blue "aura" surrounding that unit. Tapping that unit activates its special attack, which is instantly used. After finishing the special attack, the unit will continue with its standard attack until the special attack is charged again. A maximum of ten units can be in a deck in a fight.
After a sufficient length of time, a "Metal Slug Attack " (MSA) will be made available. Activating this will send a rapid-moving Metal Slug barreling toward the opposing side, exploding on impact. The MSA will run over (and instantly kill, regardless of amount of health) any light infantry, but will explode after running over ten units in a row. The MSA will also explode on impact with any vehicles or "heavier" infantry (includes Tar Men and Zombie Marco).
Two currencies are available: Metal Slug Points (MSP) and Medals. MSP is won from completing stages, and can be used to improve base qualities or increase unit health. REWARD-UPs can be used prior to starting a stage, and will increase MSP earnings by 50%, even after losing. are premium currency, and are used to either purchase tools, swap for MSP, or purchase units from the store. Players have the option of buying Medal.
Similarly to all Metal Slug games, POWs can be found and freed and reward the player with certain benefits (albeit not in the same manner). Freeing one POW for each stage in a location usually activates a special ability that improves the player's fighting capabilities, such as reducing the cooldown time for units to be produced or increasing the MSP earned from completing a stage, with each subsequent POW rescued adding on greater benefits.
At each stage completion, a letter grade is assigned to the player based on how long he/she took to complete that stage (D, C, B, A, S, from lowest to highest). The faster the player completes the stage, the higher the letter grade, and the more bonus MSP is awarded.
EMERGENCY stages will occur at certain times of the day, and appear as red locations rather than blue. These stages are accessible for a one-hour time frame, after which they disappear. Rescuing all POWs (regardless of how long it took) awards the player with a unique unit, removes the accessible time frame (making it available at all times), and unlocks the subsequent EMERGENCY stage.
In the presence of Wi-Fi, the player can access "Wi-Fi VS", which pits the player against other human players in ranked matches. Players on iOS may also play matches against friends from the Game Center. Completing matches earns points to the player's name, and match outcomes are tallied on the Wi-Fi VS home page (though opponents will only be able to view number of wins). 3 Medals are awarded to the player for every 20,000 points accumulated, and a sum of 1,000 MSP is awarded for every loss incurred.
As of version 1.5.0 of the game, a new mode has been added where you can play 2-on-2 matches that includes a chat feature. Every 5 wins in this game mode will give you 3 Medals along with the 3 Medal obtained every 20,000 points accumulated in both modes (1-on-1 and 2-on-2).
*This game recycles content from Metal Slug Wars like themes, character art & design.
*This game marks the official debut of Heidern and Whip from the King of Fighters series in the Metal Slug universe.
*This game revealed many official names of the enemies likes The Invaders, Bull Drill, Crablops and much more.
*This game filled some of the "Plot Holes" in the Metal Slug universe storyline. Such as the reason that Stone Turtle was not used in Metal Slug 5.
*While Metal Slug Defense derives its assets from the first three Metal Slugs, MSD is most heavily influenced by Metal Slug 3. Most of the game's backgrounds, units, and stage bosses as well as its ending cinematic is derived from Metal Slug 3. Recent updates adds assets from Metal Slug 5.
*This is the only game to have almost all heroes (excluding Tequilla), either as a playable character or as a cameo.
*Metal Slug Defense makes use of many previously unused sprites from the previous games like Abul Abbas attacking and the frames before he waves the white flag, Nadia eating chocolate, Natives in fire and much more.
*After clearing the first world, Satiko Suzuki will appear on the title screen. Clearing the second world will make a Mini UFO fly in the skies randomly, and clearing the third will will spawn a destroyed Metal Slug and the Di-Cokka on the ground, on the right side of the logo.Clearing more worlds such as 4-8 will appear more at the title screen (Each world makes it very hard to clear)