Isolated Watchtower

All Sliver creatures get +1/+1 for each other Sliver on the battlefield.

This artifact enters with X charge counters on it. Whenever a player casts a spell with mana value equal to the number of charge counters on this artifact, counter that spell.

Metalcraft — T: Add one mana of any color. Activate only if you control three or more artifacts.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.) Whenever you cast a noncreature spell, create a 1/1 white Monk creature token with prowess.

T: Add one mana of any type that a land you control could produce.

Commander ninjutsu UB (UB, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand or the command zone tapped and attacking.) Whenever a Ninja you control deals combat damage to a player, reveal the top card of your library and put that card into your hand. Each opponent loses life equal to that card's mana value.

At the beginning of your upkeep, you may look at the top three cards of your library, then put them back in any order.