Friday the 13th: The Game (HP)

For this achievement you will need to reach 'level 31' in order to unlock all the Jason's required and play at least 1 match with each of them. Playing matches as either Jason or the Counselors will make progress towards your overall level. Playing offline vs bots will make progress towards your level, however will not count towards the progress of the achievement - you will need to play in online versus matches for progress to count.

The Jason's and the levels in which they unlock at are as followed:

Part 3 - Starting Jason
Part 6 - Starting Jason
Part 7 - Unlock at level 7
Part 2 - Unlock at level 13
Part 8 - Unlock at level 20
Part 9 - Unlock at level 31
Part 4 - Unlock at level 44 (Not required)

Here are some tips to gaining XP in order to help level up:

As a counselor:
Interactions with Jason such as hitting him with melee weapons or shooting him with a shotgun or flares.
Stunning him with firecrackers or escaping his grasp by having a pocket knife in your inventory will also gain you XP.
Locking doors, Laying traps, using the radio to call Tommy Jarvis and repairing fuse boxes are also included as well as the obvious interactions like fixing the car/boat and escaping in either or to the police.

As Jason
Earning XP as Jason is way more straight forward and is simply done so by trapping and killing counselors in as many different ways as possible. The environment has plenty to offer in terms of environmental kills, but to name a few you can be looking to kill counselors hiding under beds or in cabinets or tents. Some cabin walls and furniture can be used for kills as well as windows, doors and fireplaces to name a few.

To unlock this achievement you will need to play a lot of matches because you will need to reach level 31 to unlock all of the Jason's.

Ways to earn xp

Fixing the boat, car, telephone, fuse boxes.

Laying traps, locking doors, picking up your first weapon.

Escaping Jason's grasp, hitting Jason with flares, firecrackers, shotgun, calling the cops.

Escaping to the cops, escaping by boat, escaping by car.

I'm sure there are a few I've forgotten but it gives you an idea.

I'm sorry to say but the Jack of all Jasons achievement in the game is no longer obtainable, and there is nothing that can be done to fix this. This achievement has been permanently broken by the latest update