From 1.3.1.3(due to the profitable food system, so maybe some of these glitches are fixed in 1.3.1.4) singleplayer, 0.9.2.1
Damage of Red Storm, Megavolt, projectiles of Divine Claymore isn't affected by damage bonus
Eternal Agony's price is too high
Shroomite Minigun's damage shouldn't be lower than megashark
The Fallen Snake's damage shouldn't be lower than Terrarian
Squasher isn't useful as either a hammer or a weapon
Crystal Spear(a magic weapon) can be stacked
Ice Bullet isn't regarded as bullet
Frostbite Chest can't be used to summon the special mimic using light/dark key
Glacier biome should use the background picture, color of water and blizzard effect of Snow biome instead of default Forest ones
Player-summoned Martian Probe neither move nor trigger Martian Madness
In a normal world, The Dark Emperor doesn't drop Soul of Fight and there is no way to get it
If the player finishes the last part of Paradox Cohort too quickly, the boss will not spawn. And no matter the boss is defeated or not, Paradox Titan Soul will not disappear.
Replaced projectile can't do critical damage every time when critical chance is above 100%(Snake Devourer, Dragon Rafale, Etherealm and "moon flames" of The Ultimate Boomstick)
Knight Zombie's initiative melee attack's range is a little bit shorter than the distance between it and the player, so its melee attack can't touch the player
Guardian armor's set bonus isn't working and it's easy to avoid(maybe every piece decreases movement speed)
Various problems about Vanity after mechanical bosses
Generation of Luminite stack and Nightmare Ore are is too much
Maybe Nightmare Ore shouldn't spawn in Surface layer, which may destroy some player-creations
Generation of Collapsium Ore and Angelite Ore can even happen on trees, stones and of course player-creations
Paratrooper's Lens isn't working(projectiles of arrows, bullets, Scrocher, Terra Blade are tested)
Health Booster and Enchanted Health Booster need a better tooltip(it doesn't tell that health regenerates when the buff is over)
In 1.3.1.3 when some kinds of food are eaten, a message in yellow will appear(like milk)
Suggestion :
Add bonus to all pets(just like what's done for the Cursed Sapling)
Add more weapons crafted by Nano Bar and Magmonium Bar (and maybe add projectile to these two blades)
Adjust many melee weapons' performance (especially their size, I know size is more difficult to adjust)