INDIE GAME / PLAY GUIDE
Islets: 16 bosses | Locations, rewards and avoiding attacks
Covers the main story, 16 bosses, directions to 60 upgrades, six ship parts and 44 achievements; remaining gaps stated · Updated 2026-10-13
Bosses unlock the next ability or route. Use rewards to choose your next destination; during a fight, prioritize tells and safe areas over your own attack count.
All 16 bosses: locations and key points
No unconfirmed HP, elemental weaknesses or recommended levels are used. English achievement boss names serve as identifiers; ground and aerial differences have separate columns.
| Boss | Location | Unlocked route/reward | Response |
|---|---|---|---|
| Grave Crawler | First island | Double Jump | Jump over the rock immediately after the legs appear in the second half. Hit with the sword during the short opening after an attack, then retreat at the next tell |
| Sky Pirates | Air route from Sky City to the next island | Route to Inverness Island | The ship is unarmed in the first encounter. Instead of trading shots, move leftward, evade projectiles and wait to pass |
| Tomb of 1000 Spirits | Tomb Ruins | Slam | Move around in time with beams rotating from the walls. While spirits fire, watch their paths from an edge and attack during transitions when movement stops |
| Buried Beast | Spirits Landing | Island core | Dodge when weapon lines form their pattern. Weapons sent straight out return along the same path; do not approach after checking only the outward pass |
| ClockMaker | ClockWorks | Island core | Check where the boss stands when turrets appear. Move to the opposite side for one roller, or the central gap for rollers on both sides |
| GrappleBot | Southwest of Sky City | Route to Eastwright Island | Bullets linger along the charge path. Do not chase the boss in the same direction; move opposite it to break away from the lingering-bullet route |
| MechaRat | Northwest of Sky City | Route to Wolfpine Island | Aim damage at the head. Rather than continually chasing the body, watch where the head returns and fire while keeping distance |
| Forgotten Grave | Rainy Plains | Island core | Watch ground waves and spikes together. Escape into the air as small spikes increase and attack the floating orb |
| Runaway Plant | Hanging Gardens | Shift Arrows | Dodge sideways at the falling cue. With two clouds, use the gap; with three, also use the central platform. Shift gradually away from pursuing vines |
| Swamp Frog | Rainy Plains | Cloud Arrows | Avoid bubbles separately from falling rocks. Wait for ceiling rocks to explode before double-jumping, and switch between forward attacks and retreating shots |
| Stone Witch | Forgotten Rots | Propeller for the ship | For one finger, dodge outward and return inward. For several, move to empty ground. Alternate dodging and double-jumping against rolling rocks |
| Defender Unit | Southeast of Sky City | Route to Cinder Island | Use dash from the second ship upgrade. Do not simply press into the ring projectiles; choose a direction and dash through |
| Rogue Bot | The Pits | Charge Attack / route toward the core | Do not stay in the center where a turret appears. Dodge sideways when two boxes converge centrally, and read the same cues in the faster second half |
| BoneGolem | BoneGolem’s Domain | Removes one seal | Dodge away from an orb's landing point, then return after it lands. Use arrows through narrow spike gaps and jump over later missiles |
| FilthPest | FilthPest’s Domain | Removes one seal | Use Cloud Arrows platforms against three beams on both sides. For two-beam attacks, also check the opposite side they do not reach when choosing your position |
| GutGhoul | Beyond the final seal | Main-story ending | Earlier boss attacks alternate; identify clock, spike and beam cues. Reuse familiar evasions during the later ship battle too |
Alternate safe areas on the ground and in the air for ground bosses
Tomb of 1000 Spirits' rotating beams, Forgotten Grave's waves and Runaway Plant's falls are difficult to evade while staying grounded. Use Double Jump or clouds and switch sword/arrows from the air.
Do not use the same dodge for Stone Witch's single finger and multiple fingers; watch open ground. When rolling-rock speed changes, avoid repeatedly pressing dodge at one fixed interval.
Check ship functions for aerial battles
GrappleBot's lingering bullets, MechaRat's head and Defender Unit's rings require different answers. Staying near an enemy is not universally correct; first determine the vulnerable part and the function needed to evade.
Dash through Defender Unit's rings with the second upgrade. Trying to cross by normal movement leaves you taking damage without using the ship's function.
Two seal bosses and the final attack transitions
For BoneGolem, return to the fallen orb's position at the right time. For FilthPest, time Cloud Arrows to create platforms above beams.
GutGhoul switches between earlier bosses' attacks. Do not assume one corner is safe against everything; change safe areas according to clock or beam cues. The second half becomes a ship battle.
Aim for victory at full health
Can't Touch This requires winning at full health. Choose the first boss or a familiar boss in Boss Rush after unlocking it.
Grave Crawler lets you practice avoiding rocks when the legs appear in the second half and hitting only after attacks. Do not confuse lowering difficulty with the Hard Boss Rush achievement.
Frequently asked questions (FAQ)
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