Here is the full list of all 44 Fire in the Goal achievements.
FirstGoal
Won a game
Score 3 goals in a single game
Use your ultimate for the first time
Grab 20 meals in a single game
Grab 20 drinks in a single game
Won a game using pistol
Won a game using SMG
Won a game using machine gun
Won a game using rocket launcher
Won a game using chainsaw
Won a game using thrower
Won a game using shotgun
Won a game using tiger
Won a game using brown bear
Won a game using sheep
Hit the ball for more than 5 times using RPG in a single game
Hexa-kill using Sharpshooter
Keep exhilarant for over one minute
Freeze over 20 enemy in a single game
Absorb over 15k damage using protection shield
Stay air for over 10 seconds
Crowd control your enemy for over 30s
Hit all the bullets while using rapid fire
Won a game without losing a single score
Won a game with over 10 goals scored
Won a game with goal difference over 10
Won a game with over 70% accuracy using rifle
Your first kill
Kill 30 enemies in a single game
Deal over 15k damage using machine gun in a single game
Hit each fragment of your shotgun for 10 times in a single game
Won a game without a single goal or assist
Won a game using moose
Finished your traning session
Won a game using polar bear
Won a game using panda
Won a game using gazelle
Won a game using puma
Won a game using piglet
Won a game using ladybug
Won a game using beetles
Won using each type of weapon once
Won using each hero once