These are good! They should make a Deck about Armed Ninja’s dad.
More colored ninjas and their transformation techniques have been revealed by the official strategy site.
SHVA-EN011 Ninja Grandmaster Saizo
Link 2 LIGHT Warrior Link Effect Monster
Links: Bottom Left, Bottom Right
Materials: 2 “Ninja” monsters
During your Main Phase: You can Set 1 “Ninjitsu Art” Spell/Trap directly from your Deck. You can only use this effect of “Ninja Grandmaster Saizo” once per turn. While this card points to a monster(s), this card cannot be targeted for an attack, also your opponent cannot target it with card effects.
SHVA-EN012 Yellow Ninja
Level 4 WIND Warrior Effect Monster
If this card is Normal Summoned or flipped face-up: You can Special Summon 1 Level 4 or lower “Ninja” monster from your hand in Attack Position or face-down Defense Position, also you cannot Special Summon monsters from the Extra Deck for the rest of this turn, except “Ninja” monsters. You can only use this effect of “Yellow Ninja” once per turn.
SHVA-EN013 Yellow Dragon Ninja
Level 8 WIND Dinosaur Effect Monster
Cannot be Special Summoned, except with the effect of a “Ninja” monster or “Ninjitsu Art” card. Once per turn (Quick Effect): You can send 1 “Ninja” monster and 1 “Ninjitsu Art” card from your hand and/or face-up field to the GY, then target up to 2 Spells/Traps on the field; destroy them.
SHVA-EN014 Hidden Village of Ninjitsu Arts
Field Spell Card
If a “Ninja” monster is Summoned to your field: You can target 1 “Ninja” monster or 1 “Ninjitsu Art” card in your GY; add it to your hand, but you cannot activate cards, or the effects of cards, with that name for the rest of this turn. If a “Ninja” monster(s) or “Ninjitsu Art” card(s) you control would be destroyed by battle or an opponent’s card effect, you can banish 1 “Ninja” monster from your GY instead. You can only use each effect of “Hidden Village of Ninjitsu Arts” once per turn.
SHVA-EN015 Ninjitsu Art of Mirage-Transformation
Continuous Trap Card
Tribute 1 “Ninja” monster, then target 1 monster in your opponent’s GY; Special Summon it to your field. It is also treated as a “Ninja” monster while this card is face-up on the field. When this card leaves the field, send that monster to the GY. You can only activate 1 “Ninjitsu Art of Mirage-Transformation” per turn.
By these mock-up images, we can infer they are all Secret Rare cards, except for Yellow Ninja.