Ismael is the first phase of the finale. He matters because he is not just another monster. He is the schemer who pushed Janosz, the relic, and the whole Dumazu problem into motion.
Where the fight happens
You fight Ismael the Deceiver during Temple of the Destroyer, in the first half of the final battle.
What “pay attention to the colors” actually means
In Ghostbusters: Sanctum of Slime, enemies and bosses can glow red, yellow, or blue. That glow is the aura color. You are supposed to switch your weapon color to match it.
- Red aura = use the red Proton Beam.
- Yellow aura = use the yellow Fermion Shock.
- Blue aura = use the blue Plasma Inductor.
If you use the wrong color, the boss usually takes little damage, so it can feel like nothing is happening. If you use the matching color, the damage starts landing properly. That is all “pay attention to the colors” means: look at the boss glow, switch to the same color, then attack.
How to beat Ismael the Deceiver in Ghostbusters: Sanctum of Slime
- Do not stand still. Start by moving in a loose circle or side-to-side path so the boss and the smaller enemies do not trap you.
- Check the boss color before you commit. If the boss is glowing red, yellow, or blue, switch to that exact weapon color first.
- If smaller enemies are swarming you, clear enough space to breathe. You do not always need to kill every add immediately, but you do need enough room to see the boss and dodge.
- Attack when the room is readable. This game gets harder the moment the screen turns into chaos. A clean few seconds of correct damage usually beats frantic wrong-color firing.
- Repeat the cycle. Move, check the aura, match the color, hit the boss, make space, and do it again.
How this fight works
Ismael is the phase where the game checks whether you can handle color switching under pressure. If he changes aura, you change weapons. Do it immediately. If you hesitate and keep the old color on him, you waste time and make the room more dangerous than it needs to be.
Think of this fight as a rehearsal for the real final boss: stay calm, read the glow, switch, hit, move.
Quick plain-English summary
For Ismael the Deceiver, the winning loop is: stay moving, do not let the arena swallow you, match the boss aura color to the same weapon color, and only go all-in when you can still see what the room is doing.
Need the full mission context? Go back to the Temple of the Destroyer walkthrough.