Goten (Kid) & Trunks (Kid) are an incredibly powerful unit capable of both dealing a lot of damage and tanking after they Super Attack. The main appeal of this unit is certainly its self-sufficiency: Goten (Kid) & Trunks (Kid)'s Passive gives them a random amount of Ki that allows them to get their 18+ Ki Super Attack consistently.
How to get
Dokkan Awaken From Plucky Little Fighters Mighty Mask.
Fusion (12-17 Ki)
Skinny Gotenks or Fat Gotenks
12-17 Ki = 50% chance for either Fat or Skinny.
Skinny: Causes colossal damage, lowers own ATK for 1 turn Fat: Causes colossal damage, lowers own DEF for 1 turn
12 Ki Multiplier
Fusion (18+ Ki)
SS Gotenks or SS3 Gotenks
18-24 Ki = 70% chance for SS1 Gotenks, or 30% chance for SS3 Gotenks
SS1 Gotenks: Causes mega-colossal damage and DEF +30% for 1 turn SS3 Gotenks: Causes mega-colossal damage and ATK & DEF +50% for 1 turn
If you want to put Goten (Kid) & Trunks (Kid) on this team, your best option is to put them together with Beyond the Ferocious Flash Majin Vegeta, since they share "Shattering the Limits" and Majin Vegeta does not require an 18+ Ki to hit hard. They can work well on this team, but they are not your prime option, [Astounding Transformation] Super Saiyan 3 Goku (Angel) is a better partner for Majin Vegeta since Goten (Kid) & Trunks (Kid) do not have "Super Saiyan". Another alternative would be to have them on rotation with [Hidden Power Unleashed] Ultimate Gohan, sharing "Shocking Speed" and leaving the majority of the orbs for Ultimate Gohan thanks to their self-sufficiency.
Goten (Kid) & Trunks (Kid) are great on this team, but they just don't fit that well: they share "Shocking Speed" with most of the other units, but not having "Prepared for Battle" or "Fierce Battle" hurts who is on rotation with them. The best option would be to have Unparalleled Super Saiyan Super Saiyan 4 Vegeta on rotation with them and have a few support units floating to have more consistency.
Goten (Kid) & Trunks (Kid) have multiple Super Attacks: their 12-17 Ki causes colossal damage and lowers their own stats, 50% chance to lower their ATK and 50% chance to lower their DEF, whereas their 18-24 Ki Super Attack causes mega-colossal damage and raises their DEF, with a 30% chance of also raising their ATK for one turn.
Goten (Kid) & Trunks (Kid) are an alternative Super AGL leader to [Unparalleled Super Saiyan] Super Saiyan 4 Vegeta: their Leader Skill gives 4 Ki instead of 3 to the element while sacrificing a 20% boost from all stats. The second part of their Leader Skill is actually superior to SS4 Vegeta's, giving 2 Ki to Extreme AGL and 70% across the board.
Goten (Kid) & Trunks (Kid) receive a 120% ATK boost when performing a Super Attack and a random amount of ki between 3 and 9. The last part is what makes them so great being self-sufficient for an LR is the best thing, not having to rely on support units or on the Ki on the board.
No “Super Saiyan”, “Fierce Battle” or “Prepared for Battle” hurts this unit, especially on Super AGL, but “Z-Fighters” and “Shocking Speed” are not bad on “Hybrid Saiyans”.
Super Vegeta shares "Z-Fighters", "Prodigies" and "Shattering the Limits" with Goten (Kid) & Trunks (Kid) and gives them 2 Ki and 25% to ATK and DEF through his Passive. By linking with Super Vegeta, Goten (Kid) & Trunks (Kid) get a total of 4 Ki, 40% ATK and 25% DEF.