In this guide I will explain how to unlock all Double Cross achievements. The game isn't particularly difficult, and most of the achievements are self-explanatory, still I wanted to provide a reference in case you're missing any.

For the purpose of this guide, I grouped the achievements as follows:

• Campaign achievements are unlocked by progressing through the story;
  
• Speedrun achievements are unlocked by completing missions within a limited time;
  
• Agents achievements are unlocked by talking to RIFT agents and completing some tasks for them;
  
• Miscellaneous achievements features the remaining ones.

Before we get to the actual guide, here is some important information:

• When you are about to submit the final "Stop Suspect X" case to Valery Wiseheart, the game warns you that you have reached a "point of no return" and that you won't be able to access the regular missions afterwards, however this is only partially true. In fact, during the final sequence, you can use the new "Reverse Sequence" option in the pause menu to get back to the "pre-case-submission" point of the story. Likewise, loading the game after completing the story brings you back to that same point. Obviously, I recommend passing the "point of no return" only after having completed all possible tasks (and achievements).

Also, here are some useful tips:

• Some equipable upgrades are particularly useful in the final stages of the game (as well as required for a few achievements), and the same goes for permanent upgrades. It is therefore a good idea to collect as much Upgradium as possible as you go through the missions, rather than dealing with it as an end-game activity.
  
• In addition to being able to give items to RIFT agents, it is always possible to talk to them (which is required for several achievements, by the way). New dialogue opportunities (revealed by a special icon above the characters having news for you) are unlocked as you progress through the story, so my advice is to always make a complete tour of the HQ between missions.

Complete the training session at the RIFT HQ training area.


Complete the first investigation after Suspect X's attack on the RIFT HQ. Specifically, you have to give the following items to the correct RIFT agents: Dimensionite Residue to Sam Squatch, Viscous Substance to Freya Gronnalva, and Misplaced Wrench to Skip Hollister. Later, go to Valery Wiseheart and submit the case.


Complete all Reptarria missions and find enough evidence to submit the "Reptarria: Smuggling" case. Evidence comes from two items:

• Hideout Map. It is obtained by comparing the Abstract Art (from Bonecrackle Canyon mission) to the maps in the RIFT HQ offices.
  
• Smuggled Weapons. They're obtained by giving the Hidden Weapons in the Sassy Crate (from Firebrand Factory mission) to Helena Lycastia. To open the Sassy Crate, you must give it a password: that's the Hidden Message inside the Reptarrian Figure (from Heavy Metal Oasis mission), found by giving the figure to Skip Hollister.

Defeat Ripjaw. the boss of Reptarria.


Complete all Funderdome missions and find enough evidence to submit the "Funderdome: Bribery" case. Evidence comes from two items:

• Evidence of Bribery. It is obtained by giving the Encrypted Disk (from Tolmekia Palace mission) to Ada Lovepaws.
  
• Ms. Ham's Testimony. It is obtained by giving the Love Letter (from Funky's Arcadium mission) to Pineapple.

Defeat Hancho, the boss of the Funderdome.


Complete all Gootopia missions and find enough evidence to submit the "Gootopia: Anomalies" case. Evidence comes from three items:

• Attack Plans. It is found in one of the lockers in the training area, after giving the Shrinking Goo (from Slimy Mire mission) to Sprout Ironbulk.
  
• Dimensional Goo. It is obtained by giving the Mysterious Goo (from Goo Grotto mission) to Sam Squatch.
  
• Experiments Logbook. It is obtained by giving the Encoded Logbook (from SPHERE Station mission) to Dash Sterling.

Defeat Freya Gronnalva, the boss of Gootopia.


After solving all 3 cases and having found all the evidence for the "Stop Suspect X" case, talk to Valery Wiseheart and submit it.


Defeat Rogue Zahra.


Defeat Rogue Dash and Dash.


At the end of the game, Valery Wiseheart visits Dash Sterling at the RIFT HQ prisons: the achievement is unlocked as soon as their dialogue begins.
BONUS TIP — For the dialogue to happen, it may be necessary to listen to all news/gossip about Dash and Valery throughout the story, but I have not verified this myself.

Complete Reptarria Mission 1, Firebrand Factory, within 15 minutes. You can check the current time in the pause menu.


Complete Reptarria Mission 2, Heavy Metal Oasis, within 15 minutes. You can check the current time in the pause menu.


Complete Reptarria Mission 3, Bonecrackle Canyon, within 15 minutes. You can check the current time in the pause menu.


Complete Gootopia Mission 1, Slimy Mire, within 15 minutes. You can check the current time in the pause menu.


Complete the Gootopia Mission 2, Goo Grotto, within 15 minutes. You can check the current time in the pause menu.


Complete the Gootopia Mission 3, SPHERE Station, within 15 minutes. You can check the current time in the pause menu.


Complete the Funderdome Mission 1, Kaneda Boulevard, within 15 minutes. You can check the current time in the pause menu.


Complete the Funderdome Mission 3, Tolmekia Palace, within 15 minutes. You can check the current time in the pause menu.

V"!!k}~X is the alien who has been arrested at the very beginning of the story. After being released from prison, V"!!k}~X can be found in the RIFT HQ lounge: to unlock the achievement, help the alien enrol in the RIFT academy, by talking to Dash Sterling and Sorgina DeLabourde (new dialogue opportunities will unlock between missions).


After Skip Hollister is accused of being Suspect X and is arrested, go to the prison and talk to him.


Listen to news/gossip from 5 characters, between missions.


Give the Mysterious Goo from Goo Grotto mission (Gootopia) to Sprout Ironbulk.


Give 10 different items to Sorgina DeLabourde.


At the end of Funky's Arcadium mission (Funderdome), Ms. Ham gives Zahra a love letter for a RIFT agent, but she doesn't know her beloved agent's name. To unlock the achievement, give the letter to at least 10 characters at the RIFT HQ.
BONUS TIP — Since given items stay in your inventory, you can still get the achievement even after giving it to the correct agent 🕶️.

Find at least 57 Upgradium pieces in the regular missions of the game.


Find all Upgradium pieces in the regular missions of the game.


Use the fireball technique to land the final blow on a boss.


Get the highest score in every minigame in Funky's Arcadium mission (Funderdome).


Reach the computer room in Tolmekia Palace mission (Funderdome) without being detected by security cameras (the green light beams scattered throughout the mission).


Complete every regular mission (the final area is excluded) without letting the health bar reach zero. Please note that falling into pits and spikes only causes you to lose some health, without compromising the achievement as long as you have enough health to respawn.


The final area of the game is the Station Core of the RIFT HQ. A checkpoint terminal can be found shortly after entering the area, you can use it to unequip all upgrades before proceeding further. The achievement is unlocked after defeating the third boss along the way.


Defeat Dash and Rogue Dash with the Glass Cannon upgrade equipped. The fight consists of 3 phases, all quite similar to each other:

1. During the first phase, you fight against Rogue Dash;
   
2. During the second phase, you face both Dash and Rogue Dash at the same time;
   
3. During the third phase, you finally fight against Dash.

The second phase is probably the most difficult, since both Rogue Dash and Dash attack simultaneously, combining different attacks. Both Dash and Rogue Dash use the same attack moves:

• Charge attack. It consists of (Rogue) Dash charging from one side of the room to the other side.
  — You can easily dodge it, even without moving.
  
• Moving laser beam. It consists of four vertical laser beams, slowly moving horizontally (first to the right, then to the left).
  — The best thing is to follow their movements.
  
• Teleport + drop kick. It consists of (Rogue) Dash teleporting in random positions in the air, to attack downwards with drop kicks.
  — You can just keep dodging whenever (Rogue) Dash performs a drop kick. Also, he never teleports to the same spot twice during the attack, so you can take advantage of this too.
  
• Floor lowering — It consists of an "indirect" attack, with the floor lowering beyond the horizontal laser beam at the bottom end of the room, and three anchors descending from the top end of the room.
  — Just use the three anchors while waiting for the floor to rise again.
  
• Homing energy orb — It consists of an energy orb that gradually moves towards Zahra.
  — I have never been able to dodge this attack consistently, so my advice is to lure the orb to the opposite sides of the room and then go around it with a wall jump.
  
• Wheel of small energy orbs — It consists of 8 small energy orbs around (Rogue) Dash, which are thrown at Zahra after the highlighted orb completes two turns.
  — You can defuse the attack by "catching" the highlighted orb with the proton slinger, before it completes two turns.

BONUS TIP — There's a checkpoint terminal right before the boss room, so you can equip the Glass Cannon right before the boss fight (rather than at the start of the final area). For the two remaining upgrade slots, the Shield upgrade and Heavy Hitter upgrade are highly recommended.


Unlock all other achievements.

Thank you for reading this far, I really appreciate it!
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