Here is the full list of all 26 Stardust Vanguards achievements.
Complete all 10 survival waves on easy difficulty.
Complete all 10 survival waves on medium difficulty.
Complete all 10 survival waves on hard difficulty.
Complete all 30 survival waves in endurance mode.
Play a custom battle with insane amounts of reinforcements.
Play a custom battle with infinite ammo.
Get a tri-kill.
Call a 100 RP squadron into battle.
Complete a round of deathmatch.
Deflect a bullet into another player.
Complete a round in the "Grid" arena.
Complete a round in the "Colony Attack" arena.
Complete a round in "Stadium Epsilon."
Assassinate a VIP unit.
Win a round while also being a bounty target.
Lose an entire war to the pirates.
Play a match of Space Ball.
Get a "Most Boring" post-battle status (have no other statuses).
Get a "Pyrrhic Victory" post-battle status (win with the most troop losses).
Get a "Sacrifice" post-battle status (your team won while you were eliminated).
Get an "Honorable" post-battle status (never fire bullets).
Unlock all arenas, stadiums, and game modes.
The green team wins a single battle.
The red team wins a single battle.
The blue team wins a single battle.
The yellow team wins a single battle.