First and foremost...who cares?
Answer: Anyone wishing to use Henchman as troops. I read a recent article lately that just did not do service to the Grey Knight (GK) elite choices. So, I had to throw my two teef' into the mix.
I will focus on Jokero's today. Why are they good? They cost 35 points each, which is steep for such low stats. What they do bring is flexibility to the unit and offer quite good force multipliers.
With the ability to fire a their weapons as either a Lascannon, Multi Melta, or Heavy Flamer they offer ranged anti tank/Monstrous Creature (MC), effective mid range anti tank/MC, and effective anti infantry at close range. Their Ballistic Skill (BS) is only a 3 (meaning they hit on 4+ on a d6) but when taking 2 and outfitting the rest of the Henchman unit with the Jokero's abilities in mind they are fairly reliable.
But, the gold is found in the force multiplying d6 table they offer. First you must read the rules for the table and like many Games Workshop rules, it can be confusing. I address the d6 table rules regarding the roll of a 6 on a d6; which states: "Roll two more times on the table and apply both results, ignore duplicate rolls and further rolls of 6". Also, you need to know that for each Jokero after the first you add +1 to your rolls.
Right off there is a question; does "ignore" = "lost" for duplicate rolls. Commonly accepted English would indicate a reroll until you obtained a result you could not ignore. Whichever way your group or you decide to interpret it until a Frequently Asked Question (FAQ) document is released by GW you need to take this into account when you decide how many of these guys to put into a unit.
If you interpret the rule in the more restrictive way; One is the magic number. Too many rolls are lost to duplication with even one more Jokero. If you favor the other interpretation; Two is the magic number.
I have rolled the table about 500 times the last two weeks. I have found with two Jokero and rerolling or ignoring duplicate results leads to a fairly consistent (70%) output of either increased range, increased armor, or rending on non template weapons. I typically roll for three squads. Almost every time ends up with one of each of rending, range and either armor improvement or 5+ invul. Many times two good rolls are applied as you only need a 5 or 6 to receive the two rolls result.
One Jokero results in about 50% of getting either range, rending, or increased armor. With both examples I tend to roll rending, armor, and range most often and in that order.
So, with all that said I build my squad with this in mind. Warrior Acolytes get Flak Armor (4+save), Storm bolters, 3 with melta...plasma gun to taste, and if going to contain an inquisitor most likely a Ordo Malleus with Psycannon, and a combination of Multi melta and Heavy Bolter. Relatively inexpensive for the damage potential.
Two good rolls...range and armor .... would end up with 3+ saves for the majority, 60" Lass cannon, effectively your melta guns to multi meltas giving you 5 when combined with the two Jokeros, 36" storm bolters, and a 36" Psycannon....ouch! You can extrapolate if you roll for rending, or even range and rending. In fact just a bargain basement version of 10 Flak armored storm bolter armed Warrior Acolytes and two Jokeros could turn into 36" rending storm bolters...very nice (Out of 500 rolls I have rolled this 35 times or about 1 in 14)
Each squad can catch a ride in either a hard to shake/stun rhino or a Chimera with better front armor and 5 slots to shoot from.
Thanks for the read,