Heister

Your skills are built around scoping out, understanding and finding ways around the defences of secure locations; often ones holding valuable loot or information. Usually on the wrong side of the law, you understand the importance of a smooth heist, reliant on a good plan, in order to avoid arrest. Like how an old soldier never dies, a good heister will remain uncaught, provided they don't get cocky, so know when to retire.

Master of Reconnaissance

Starting at 3rd level, you get proficiency in perception and a gaming set of your choice, plus you now gain advantage on perception checks using spyglasses/binoculars. In addition, you now gain the ability to spend an action to do a perception check against a target's constitution save, in order to spot a weak spot; which will grant you or a teammate you call it out to advantage on their next attack roll against it.

Networks & Schemes

By spending a 7 days (disadvantage), 14 days (normal) or 21 days (advantage) of off-time looking for new criminal contacts, you can roll a persuasion check to gain one or more contacts in the field you specified. Only if your result is a 1 do you attract the attention of the law, otherwise anything below 10 will result in a sub-par or lacking result, while 10 or above will result in an suitable and fulfilling one; with the exact details of this result, and the character, being up to the DM's discretion. The more specific you are in terms of what you're looking for, the more likely you'll get a good result.

Additionally, by spending an hour to prepare plans to infiltrate a specific location, take on a specific enemy (or group of enemies), or otherwise execute something dependent on a plan; you get to start accumulating planning points, the maximum you can earn per day equal to your intelligence modifier, to a minimum of one per day. These points will be stored and can be spent when pulling off the plan, in order to do a number of actions that will improve your chances of success, unlocking more as you level. Initially, you may spend 1 planning point to add (an additional) proficiency bonus to a check related to the plan, or you may spend 3 planning points to gain advantage on a check related to the plan. You may instead grant the effects of these to a teammate if you so desire, at the cost of 1 extra planning point.

Takedown Expert

Starting at 9th level, you gain advantage on grappling or otherwise pinning down unaware targets.

You will also be strengthened against surprised enemies, gaining advantage on attack rolls and critical hits against them will now grant an additional damage. Provided you use normal critical hit rules, you get to roll the damage die/dice an additional time; while in the case of the alternate critical hit system, where a critical hit deals what damage you rolled plus the max possible value on the damage die/dice, you double the damage from the max possible damage of the die/dice.

Additionally, you gain the ability to equip, fire and then stow a number of loadable weapons, equal to your dexterity modifier (unless it is negative, in which case this ability can't be used); allowing you to rapidly fire numerous prepared weapons whenever you need it, however, these weapons will have to be reloaded normally. Lastly, light throwable weapons that would usually require an action to be thrown, can now be thrown with only a bonus action, potentially working in tandem with the previously mentioned ability.

Calling Card

A calling card is a recognisable sign of a particular person or group's involvement, left at a crime scene as a way of taunting law enforcement and/or claiming responsibility. Beginning at 13th level, you gain the ability to regain a number of planning points, at the DM's discretion; if you leave one.

You must also make the choice between Flexible or Thorough planning.

Flexible Planning

Allows you to continue using the abilities as normal, even if the plan goes wrong and has to change, with double the price. In addition you also get an ability to dump all the current planning points in exchange for healing, allowing you to roll a number of stored hit die to regain health, equal to the amount of points discarded. If you discarded more planning points than you need (or want) healing, you may instead distribute this effect to teammates, though they would still have to roll with your class' hit die. This choice allows for failed or changed plans to go somewhat back on track, instead of ending in catastrophe.

Thorough Planning

Replaces the proficiency you'd get by spending 1 planning point, with expertise instead, doubling it's worth. You will also be allowed to spend 5 planning points to either gain triple-advantage on an upcoming roll, or to re-roll a failed throw (or just one who's outcome you're not happy with), though regardless of whether you had advantage or not on this roll you will only get to re-roll one die. This choice allows for more efficient plans, with less chance to fail in the first place.

Infamy

Starting at 17th level, you gain the ability to retroactively change and add details to your plan, as if they were always part of the plan. By doing this you can either just stretch the framework of which your planning abilities work in, if they otherwise wouldn't apply due to surprises or changes, at the cost of 4 planning points; or you can add an item to your inventory (retroactively paying for it too), reveal you actually told a character or NPC a certain thing, or you can change the environment to your advantage; like revealing you actually placed a trap at the exact spot the enemy is standing, at a planning cost based on the DM's discretion.