So an ability that is only usable after a few turns of powering it up? Seems like a space worth exploring.

This implementation, with multiple abilities, is completely impractical though.

I turn this card sideways and... uh, which tokens go where? Everything's fallen off!

The obvious alternative is better, but leads to "So, it has 1 green and 2 red tokens, and... was green the top ability or the bottom one?"

Works fine as an electronic implementation, though (although it does still suffer from significant complexity in understanding what card can do what)

Actually, I now realize this is much less clear than it was in my head, and that I should have put in a descriptive paragraph.

The circles are a way to represent cooldowns. Ability counters start on the leftmost circle, and the costs, such as "2→," represent moving the counter two spaces to the right. If there aren't enough spaces remaining to the right, the cost can't be paid. The counters move back to the left as turns pass.

Sigma here gives a "simple" example, since both cooldowns use the whole track. Ana Amari presents two more complicated takes. Her first two cooldowns use the same track, and her second cooldown can be used twice in one turn, given that it starts all the way to the left, since there's ample space on the track.

You're right, though, in that this is probably impractical for tabletop Magic even though it's borrowed from board games.

So:

• Sigma starts with a counter on the bolded space of each track.
• The counter is moved to the right as part of the cost of activating the ability.
• Each turn, as you untap permanents, you move each of your cooldown counters one step left.

Ok, so usable after charging; but with an alpha-strike capability :)

To fix it to be usable in magic; untie it from untapping. Put it on things that don't tap, and most of the problems go away.

And, uh, then you end up re-creating planeswalkers. Stupid planeswalkers.

I think the free first activation is a problem - at least for some abilities. Also a card with multiple tracks can hardly be considered the "'simple' example".

I think it is worth exploring this. It's a bit like the old "double tap" ability, but the fact that it is so entirely independent from tapping also means the decision to use the ability has less interaction with the existing game mechanics.

I feel a teensy bit of interaction with existing mechanics would be nice e. g. only moving back on the track if you are already untapped, so using your "charges" and attacking in the same turn is not entirely free.

Riffing on the idea: Double-Axe Veteran, Disciple of the Mindwarper, Druid of Kadava & Vortex Sage.