In today’s guide, we’re covering Ys: The Oath in Felghana How to Defeat Istersiva. To be more precise, Istersiva, the Crystalline Entity, is the fifth boss in the came. You’ll come across it in the second dungeon, the Abandoned Mine. This boss has 2,000 HP and it’s recommended that you reach at least Level 23 before facing it. Don’t forget to also upgrade your Shield, Broadsword, and Plate Mail, if you own it. Continue on to learn more about Istersiva’s attack pattern and how to defeat it.
Istersiva’s Attack Pattern
There are two phases to the battle with Istersiva. To begin the fight, Istersiva will do a Poison AOE attack, where it’ll splatter poison around it. Dodge the poison and stand in a clean area. Istersiva will also pull its head back before slamming into the ground and creating a shockwave. The moment you see it rise, move away from it. Istersiva frequently burrows into the ground and reappears, giving you the chance to attack it when it’s not moving.
Istersiva also has the ability to summon little minions that will fire beams at you. You’ll want to take them out when they appear since they can be a real nuisance.
During the second phase, the boss will start by throwing exploding orbs at you. Run to the side to avoid this. It relies heavily on this attack and the amount of orbs will only increase as the battle continues. Standing in the empty areas and using Double Boost to replenish your health is the best strategy.
How to Defeat Istersiva
Don’t let the number of minions pile up, or you’ll start taking damage from too many different directions. Make sure they’re all gone before the second phase of the fight. Attack Istersiva whenever it emerges from this ground since this presents a good window of opportunity. During the second phase, aim for its backside. It’ll also open up its crystal shell, giving you the opportunity to attack and deal heavy damage.
That’s it for this Ys: The Oath in Felghana How to Defeat Istersiva. Need more game guides? Check these out!
Has been playing video games for her entire life so far. Grew up with the Sega Master System II. Her favourite games include both Resident Evil 2 (OG) and Final Fantasy VIII.
She now writes articles about video games.
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