We aim to provide some basic information about the combat in this SLIME – ISEKAI Memories Basic Battle Guide to help you to understand the combat quicker, most of information is translated from xiaoguiyo’s excellent guide, all credits to him, and appreciate him allowing us to repost and translate it.
Combat Interface Basic Functions
SLIME – ISEKAI Memories utilizes turn-based combat, there are types of combat modes, Normal Battle & Predator Battle
Normal Battle

1. Protection Skill
Protection Skill is unique to the leader of the team, the Protection character, the gauge needs to be full in order to activate, you fill the gauge by using Protection Abilities from your attack slots.
2. Character Skill
Character Skills are the skills unique to each Battle Character, most skills are buffs in nature, such as ATK increase, DEF decrease, DEF increase, Healing, Skill Swap. You need to spend a specific amount of skill points when you use a Character Skill, maximum amount of Skill Points you can accumulate is 100. As you use a skill, the points required to use the skill increases, e.g. 35->55->75.
3. Normal Attack Slot (Protection, Skill, Secret Skill)
Normal Attack Slots consists of 3 types: Protection, Skill, Secret Skill, you can select the cards based on the situation at hand, to decide the respective gauges to fill.
4. Target Select
Selecting the default attack opponent, long pressing will display information about the target.
5. Speed, Auto, Menu
Speed toggles between different battle speeds
Auto toggles between auto and manual combat
Menu, some basic settings, e.g. retiring/quitting the battle
6. Switch Characters
Can switch to the 2 backup characters (needs to be assigned beforehand), backup characters will automatically join the battle if one of your 3 primary characters die.
7. Activate
Once you’ve selected the cards from the attack slot, you can activate the attack here.
Predatory Battle
There aren’t that much difference between Normal Battle & Predatory Battle, except here the enemy won’t die, instead you’re trying to fill the gauge to try and increase your odds of capturing it.

Please note, the gauge will decrease when you’ve taken damage.
Protection, Skill, Secret Skill Techniques
1. Protection
Protection Characters are the team’s leader, different characters have different Protections, using characters with the same attributes will provide buffs to the respective Battle Characters.

Filling the Protection Gauge in battle will activate that Protection Character’s unique Protection.

2. Skill
Skills are Battle Character’s unique abilities, most are buffs in nature such as decrease opponent’s DEF, increase party’s ATK, and healing, the skill points required increase as you use the skill.
3. Secret Skill
Secret Skills are the ultimates of that particular character, when Secret Skill is filled, it will turn rainbow, and you’ll be able to activate it, Secret Skill can be used along with Protection or Skill as combos.

Since the Secret Skill can be used as a combo, you can use it to assist in filling a particular gauge, e.g. if i wanted to fill my Skill gauge, I could select it along with my Skill cards like this

Or if I wanted to increase 1 particular character’s gauge, I can use it like this

or try to go for all 6 to try and get a One Turn Kill

It really depends on the situation at hand, I generally just pick which ever is most on hand.
Attributes Counter-Balance
There are 7 attributes in the game: Fire, Earth, Space, Wind, Water, Light, Dark, and they each counter another
Fire counters Earth
Earth counters Space
Space counters Wind
Wind counters Water
Water counters Fire
Light and Dark counters each other

If you can use a team that consists of an attribute that counters a particular quest’s opponents, it will greatly increases your chances of clearing the quest.
Author: 和我墮入狂賭之淵吧 (xiaoguiyo)
Original Source: 【攻略】戰鬥界面基本介紹(基本功能/加護、技能、奧義操作/屬性相剋)
Translated & Edited by Simvaio with permission from Xiaoguiyo