activating abilities

[Avodroc13]

My friend runs multiple {Kiora's Follower} sorta like additional mana. Let me explain:

2 green, 2 blue, and 1 kiora's follower on the field. Can he successfully cast {Future Sight}?
He taps the mana, then WHILE PAYING for a card he taps the follower to untap the blue to continue paying for future sight. I thought you couldn't tap creatures (for abilities) to cast spells... So to avoid this argument he does this:
Taps 2 blue and 2 green and says he's "floating" that. Then proceeds to tap the follower to untap a blue and retaps the blue so he now has 5 mana in his mana pool. Then plays future sight...

I don't know if this is legit, but can someone clarify?

[Splicer]

Well technically he can't do that while casting the spell BUT he can float the mana and then activate the follower's abillity, then tap the land again for more mana.

Tl,dr yes, he can do that.

[Avodroc13]

Also when I choose to drain mana from his mana pool into mine he taps all his unused mana to "float" (since mana burn isn't a thing anymore) so I cannot drain it into mine. There has to be a limit to prevent him from doing this otherwise a bunch of cards are completely useless.

[Splicer]

Also when I choose to drain mana from his mana pool into mine he taps all his unused mana to "float" (since mana burn isn't a thing anymore) so I cannot drain it into mine. There has to be a limit to prevent him from doing this otherwise a bunch of cards are completely useless.

Please give an example?

[LinkCelestrial]

Also when I choose to drain mana from his mana pool into mine he taps all his unused mana to "float" (since mana burn isn't a thing anymore) so I cannot drain it into mine. There has to be a limit to prevent him from doing this otherwise a bunch of cards are completely useless.

Sounds to me like he's giving you more mana...what card are you draining with?

[griffin131]

Also when I choose to drain mana from his mana pool into mine he taps all his unused mana to "float" (since mana burn isn't a thing anymore) so I cannot drain it into mine. There has to be a limit to prevent him from doing this otherwise a bunch of cards are completely useless.

There aren't many that drain mana, but yes - the ones that do you can usually float mana in response.

Keep in mind he's tapping lands to create mana, not tapping mana. There's a large difference.

[Avodroc13]

{Mana Web} is an example. He taps 1 mana and instead of all his mana becoming tapped he decides to tap all of it to "float" so he can cast more than just one spell.

[Avodroc13]

Also when I choose to drain mana from his mana pool into mine he taps all his unused mana to "float" (since mana burn isn't a thing anymore) so I cannot drain it into mine. There has to be a limit to prevent him from doing this otherwise a bunch of cards are completely useless.

Sounds to me like he's giving you more mana...what card are you draining with?

The card is {Drain Power}.

[Kaylesh]

Also when I choose to drain mana from his mana pool into mine he taps all his unused mana to "float" (since mana burn isn't a thing anymore) so I cannot drain it into mine. There has to be a limit to prevent him from doing this otherwise a bunch of cards are completely useless.

Sounds to me like he's giving you more mana...what card are you draining with?

The card is {Drain Power}.

Well, that card forces him to "float" from all his lands actually. He can still respond with instances before his mana drains to you though. Any mana that isn't used to cast spells before drain resolves, goes to you.

[Kaylesh]

{Mana Web} is an example. He taps 1 mana and instead of all his mana becoming tapped he decides to tap all of it to "float" so he can cast more than just one spell.

In this case, he taps the lands in response to the trigger, which is totally legit. It does force him to spend this mana in this phase though.

[LinkCelestrial]

If it takes the mana from his mana pool, you get it. When he floats his mana, it's in his mana pool.

[Avodroc13]

If it takes the mana from his mana pool, you get it. When he floats his mana, it's in his mana pool.

But with {Drain Power}, if he can just tap all his mana, what's the point? (Ie: Tap everything to cast a spell.)

[AwaySinceMirage]

The point would be (one possible point would be), you are making him "use it or lose it (to you)" on your main phase ({Drain Power} being a sorcery); he would have nothing left for your combat, post combat main, and end phases. Might be just the ticket you need even if you end up getting none of his mana.
Drain Power was a specialty of mine in Alpha days.

[redwolv]

If it takes the mana from his mana pool, you get it. When he floats his mana, it's in his mana pool.

But with {Drain Power}, if he can just tap all his mana, what's the point? (Ie: Tap everything to cast a spell.)

If i understand it would work like this

1. Cast {drain power} placing it on the stack.
2. He can then tap lands and cast instant speed spells in response and activate abilities.
3a. He taps lands for mana and casts a spell at instant speed
4a. Stack resolves, {drain power} taps all untapped lands then the mana in his mana poolsis yours, had he used all the mana casting his spell sadly you're out of luck.

3b. He taps all lands in response (for example purposes he floats {W}{B}
4b. DP resolves, there is no land to tap but it sees there is {W}{B} in his mana pool and gives you it.

As for the point of DP if he uses the lands to cast a spell in response, thats like asking the point of casting a spell only to have your opp {cancel} it. The point is the attempt and (hopefully successful) execution of it.

[LinkCelestrial]

What you're not seeing is that all the mana he floats is in his mana pool so you get it. For example.

You {Drain Power}

He has 2 {Forest} and 3 {Mountain}.

In response he taps all his land, putting {G}{G}{R}{R}{R} in his /mana pool/.

He could then spend that mana on say, a {Lightning Bolt}. Then he has {G}{G}{R}{R} in his mana pool.

{Drain Power} resolves, taps his lands (which are all tapped) then you get his {G}{G}{R}{R} that he floated because you're taking mana from his mana pool and that's where mana goes when you float it.