If you would create a Clue, Food, or Treasure token, instead create one of each.

Whenever you cast an artifact spell, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.") Activated abilities of artifacts you control cost {1} less to activate. This effect can't reduce the mana in that cost to less than one mana.

Woman Who Walked the Earth — When Martha Jones enters, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.") Whenever you sacrifice a Clue, Martha Jones and up to one other target creature can't be blocked this turn. Doctor's companion (You can have two commanders if the other is the Doctor.)

Living weapon (When this Equipment enters, create a 0/0 black Phyrexian Germ creature token, then attach this to it.) Equipped creature gets +1/+1 for each artifact and/or enchantment you control. Equip {2}

{T}, Sacrifice an artifact: Draw a card.

Enchant creature Enchanted creature gets +1/+1 and has "Whenever this creature deals combat damage to a player, investigate." (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Flying Whenever you investigate for the first time each turn, investigate an additional time.

Flying When this creature enters, investigate X times, where X is the number of opponents you have. (To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.") Whenever you draw your second card each turn, create a 1/1 white Spirit creature token with flying.

Commander creatures you own have "{2}, Sacrifice an artifact: Put a +1/+1 counter on this creature and draw a card."

Echo {4} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.) Sacrifice an artifact: Put a +1/+1 counter on target creature.

When this enchantment enters, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.") Whenever you sacrifice a Clue, target player mills three cards.

{T}, Sacrifice an artifact: Target player mills three cards. Whenever an artifact enters, you may untap this artifact.

You have no maximum hand size. Sonic Booster — Whenever Nyssa of Traken attacks, sacrifice any number of artifacts. When you sacrifice one or more artifacts this way, tap up to that many target creatures and draw that many cards. Doctor's companion (You can have two commanders if the other is the Doctor.)

{T}, Sacrifice one or more artifacts: Choose a color. Target player adds three mana of the chosen color for each artifact sacrificed this way.

A player who controls more permanents than each other player can't play lands or cast artifact, creature, or enchantment spells. That player may sacrifice a permanent of their choice for that player to ignore this effect until end of turn.