Mana Bloom enters the battlefield with X charge counters on it.
Remove a charge counter from Mana Bloom: Add one mana of any color. Activate this ability only once each turn.
At the beginning of your upkeep, if Mana Bloom has no charge counters on it, return it to its owner's hand.

Counter target spell. At the beginning of your next main phase, add an amount of equal to that spell's converted mana cost.

Flying, trample
Join forces — Whenever Mana-Charged Dragon attacks or blocks, each player starting with you may pay any amount of mana. Mana-Charged Dragon gets +X/+0 until end of turn, where X is the total amount of mana paid this way.

Gain control of target creature until end of turn. Put a +1/+1 counter on it and untap it. That creature gains haste until end of turn. (It can attack and this turn.)

Target creature gets +1/+1 and gains flying until end of turn.
Jump-start (You may cast this card from your graveyard by discarding a card in addition to paying its other costs. Then exile this card.)

Trample
Melee (Whenever this creature attacks, it gets +1/+1 until end of turn for each opponent you attacked this combat.)

Return up to two target creature cards from your graveyard to your hand.

Deathtouch

Counter target spell. Create an X/X green Ooze creature token, where X is that spell's converted mana cost.

Take an extra turn after this one.
If Nexus of Fate would be put into a graveyard from anywhere, reveal Nexus of Fate and shuffle it into its owner's library instead.

Exile an instant or sorcery spell you control: Put two +1/+1 counters on Nivmagus Elemental. (That spell won't resolve.)

You don't lose unspent green mana as steps and phases end.
Omnath, Locus of Mana gets +1/+1 for each unspent green mana you have.

Oran-Rief, the Vastwood enters the battlefield tapped.
: Add .
: Put a +1/+1 counter on each green creature that entered the battlefield this turn.

Put target creature into its owner's library second from the top. Its controller gains 3 life.

Flying
When Peregrine Drake enters the battlefield, untap up to five lands.

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
If damage would be dealt to Phyrexian Hydra, prevent that damage. Put a -1/-1 counter on Phyrexian Hydra for each 1 damage prevented this way.

Protection from everything
If Progenitus would be put into a graveyard from anywhere, reveal Progenitus and shuffle it into its owner's library instead.

When Quakefoot Cyclops enters the battlefield, up to two target creatures can't block this turn.
Cycling (, Discard this card: Draw a card.)
When you cycle Quakefoot Cyclops, target creature can't block this turn.

Whenever a card is put into your graveyard from anywhere, you may put a quest counter on Quest for Ancient Secrets.
Remove five quest counters from Quest for Ancient Secrets and sacrifice it: Target player shuffles their graveyard into their library.

Whenever an opponent discards a card, you may put a quest counter on Quest for the Nihil Stone.
At the beginning of each opponent's upkeep, if that player has no cards in hand and Quest for the Nihil Stone has two or more quest counters on it, you may have that player lose 5 life.