Discussion Forum

I guess the card preview didn't work like I thought it would... be gentle... it's my first time...

One or two years ago all html-codes got stopped due to some problems on this site so, sadly, there is no card-preview.

1.) The only way a tap-effect, like "Conspire", can activate another card would be the text "whenever this card becomes tapped", like "Insolence" or "Judge of Currents". Unless you have any effect like this you can only use either a creatures own tap-ability or use it for the Conspire effect.
I'm quite sure that you misunderstood something about effects like "Conspire" and tap-ability's: You don't need a creature with a tap-effect to use it for such effects, any creature can be used for this effect (Like some simple 1/1 tokens). They also don't require you to wait a turn for the summoning sickness to wear off as you're not using the creatures own ability (if they have any) but tap it for some other effect.

2.) No, you can't cast a spell or activate an ability without being able to legally declare a target for that spell or ability.
If you want further information see rule 601 (Casting Spells), 602 (Activating Activated Abilities) and 720 (Handling Illegal Actions) in the complete rulebook.
In the case of Karplusan Yeti: It doesn't say that you have to target one of your opponents creatures. The Yeti is even able to target itself.