Destiny 2's Bastion was released on January 28th, 2020, which is an Exotic quest for those who have purchased the Season Pass for Year 3's Season of Dawn. Bastion is a Kinetic Fusion Rifle that includes the Breakthrough perk, which lets the weapon’s damage bypass elemental shields, and the Saint’s Fist perk which lets players charge the weapon to fire three spreads of Kinetic slugs.

 
 

How to get Bastion in Destiny 2 in brief (Here's a quick rundown of the steps needed to obtain Bastion:)
1. Either talk to Osiris and complete the Corridors of Time quest, or complete Saint-14's 'Recovering the Past' and 'An Impossible Task' quests
2. Talk to Saint-14 and start the 'Momento' quest
3. Kill five Fallen Captains or Servitors in the Tangled Shore
4. Run the Empty Tank Lost Sector and kill a specific enemy, Aksiniks
5. Complete 10 Spider Bounties, and in Tangled Shore, kill 30
This step takes the most grinding: it should take about 1-2 hours to tick off these objectives. When it comes to killing 30 challenging enemies, this'll come naturally, especially if you pursue Heroic public events over standard events. The public events can be condensed to four Heroic ones instead. While you're doing all this, pick up some Spider bounties and clear them, too. Thankfully the bounties aren’t limited to his dailies, so take on some Wanted bounties to speed things along.
 
6. Challenging enemies and 8 Public Events
7. Find the grave within the Trapper's Cave Lost Sector
8. Run a special version of The Hallowed Lair strike and kill a specific enemy, Defiled Reysk
 
How to start the Bastion quest, Memento
Originally, you had to complete a 30-room sequence in Corridors of Time to start the Bastion quest. Fortunately for players who weren't on the front lines, all you have to do now is talk to Saint-14 in the Tower, apparently after completing the Season of Dawn campaign missions to save him. However, the Corridors of Time will still be open through January 28, and we recommend navigating the lengthy path just to reach the lore moment at its end.  For those who are looking to make the trek, here's the 30-room sequence. Just enter the portals marked by these symbols in the following order. Clover, Diamond, Snake, Clover, Plus, Plus, Hex, Hex, Hex, Plus, Diamond, Plus, Snake, Diamond, Clover, Snake, Plus, Plus, Snake, Snake, Hex, Diamond, Clover, Plus, Diamond, Hex, Hex, Diamond, Plus, Diamond.
 
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