The only limit is that Klauth's mana must be used on spells, not abilities, but that won't matter much in a typical Dragon deck
[Deck Title= Mono-Green Nissa Baker Neenan] [Creatures] 2 Walking Ballista 3 Smugglers Copter 2 Hydroid Krasis 4 Llanowar Elves 3 Tireless Tracker 4 Elvish Mystic 2 Emrakul, the Promised End 4 Burning-Tree Emissary [/Creatures] [Spells] 3 Oko, Thief of Crowns 3 Leyline of Abundance 4 Once Upon a Time 4 Nissa, Who Shakes the World [/Spells] [Lands] 3 Nykthos, Shrine to Nyx 8 Forest 3 Yavimaya Coast 4 Botanical Sanctum 4 Breeding Pool [/Lands] [Sideboard] 1 Reclamation Sage 1 Spell Pierce 2 Disdainful Stroke 2 Natural State 2 Negate 2 Scavenging Ooze 3 Veil of Summer 2 Grafdiggers Cage [/Sideboard] [/Deck] [Card]Burning-Tree Emissary[/Card] and [Card]Leyline of Abundance[/Card] plus Nykthos is a lot of mana but not necessarily a ton of consistency
Hybrid cards only count as multicolored if they include more than one color in their casting cost
I stretched the mana to get the power of Llanowar Elves, even if twelve turn 1 green sources is two or three fewer than Im comfortable with
Thats what happened this month to Virtus the Veiled, which is one of the best Assassins that players can copy using Altar Ibn-La'Ahad, a new commander from Universes Beyond: Assassins Creed
