These require some skill otherwise this will be an endless grind. I managed to do these legit but you can party up with a friend, queue 1v1 quick play and have them to be afk.

Just keep playing the game and eventually you'll get there.

In my opinion for these achievements and just in general I recommend opening the "Basic Pack" because for the same price as a "Gold Pack" you get 10 cards and you have 50 bucks to spare. And that "Guaranteed 1 Rare card" isn't really worth an additional 300 bucks.
































Keep opening up those "Basic Pack" and you'll eventually unlock and max out all your cards. But if you're struggling to unlock that last one or two cards you can recycle 10 "Basic Pack" for a "Collectors Pack", open that up and you'll get one of the cards that you're missing.

Walk off the edge and fall to your death. This can easily be done on Rooftop and Tabletop, not sure if Trucks and Moon counts towards this.
Repeat the same instruction above.
Head down to the shooting range, grab a gun and shoot the goose behind the counter.
Recommendation:
The score has to be 2-2 in a match and then you have to die at the same time in the last round. Easiest way to do this is to activate "Self-Destruct Device" and before you activate "Self-Destruct" to explode within their proximity, shot them a couple of times with your gun to make sure they die by the explosion.















Cards required by opponent:
When your opponent throws a bomb you'll have to shot it before it touches the ground.




















Cards required by opponent:‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ Cards required by you:
Make sure to have "Helmet" ready in your hand and activate after your opponent activates "Albatross21", then you just have to hope they can hit headshots.
Cards required by you:
Throw your own "Karrotov" at the ground and stand in it until you're dead.




















Cards required by opponent:
You need to get a "Sticky Bomb" stuck to your character, have your opponent close to you and not full HP for them to die.



















Cards required by opponent:‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ Cards required by you:
Easiest way to trigger this is for you to also have any weapon in your hand, activate that and hope for your opponent to activate "Swap Weapons" so you can swap back directly after.
Cards required by you:
Play as "Haru" to get the "Runner" speed boost then have all of these cards available in your hand. Activate both "Ninja Log" and "Move Faster" right when the round starts. Then you want to get hit by your opponent to trigger "Ninja Log" and when that happens activate "Energy Drink".
Cards required by you:
Have both of these cards available in your hand, first activate "Titan" and then "Ice Block"
Cards required by opponent:‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ ‎ Cards required by you:
Both of these needs to be activated in the same round. Once you're on the moon you have to enter the ice cream truck that is floating somewhere on the level.
Cards required by opponent:
When your opponent activates "Heartless" they drop their heart on the map, as soon as you see that their HP start ticking down you want to trace down that heart and shoot it to kill your opponent.