Roiling Canopy

put a Forest onto the battlefield — 85 cards in the game can cause this.

When a Forest enters thanks to:

1. Staff of Titania — Roiling Canopy gives +3/+3
2. Neverwinter Dryad — Roiling Canopy gives +3/+3
3. Verdant Kraken — Roiling Canopy gives +3/+3
4. Awaken the Woods — Roiling Canopy gives +3/+3
5. Mwonvuli Acid-Moss — Roiling Canopy gives +3/+3
6. Wood Elves — Roiling Canopy gives +3/+3
7. Everbark Shaman — Roiling Canopy gives +3/+3
8. Silverglade Elemental — Roiling Canopy gives +3/+3
9. Seedguide Ash — Roiling Canopy gives +3/+3
10. Casal, Lurkwood Pathfinder // Casal, Pathbreaker Owlbear — Roiling Canopy gives +3/+3

75 other cards cause it too. These are the ones with the most connections.

a land enters the battlefield — 1,542 cards in the game can cause this (Roiling Canopy is one).

When Roiling Canopy enters:

1. Primeval Bounty — gains you 3 life
2. Dancing from Dark to Dawn — makes a token
3. Toph, Earthbending Master — puts a counter on a permanent
4. Emeria Shepherd — brings a card back
5. Quest for the Necropolis — puts a quest counter on itself
6. Soul Stair Expedition — puts a quest counter on itself
7. Nissa of Shadowed Boughs — puts counters on a permanent
8. Thranduil, Sindarin Liege // Silvan Rally — makes a token
9. Silvan Reveler — returns itself from the graveyard
10. Floral Evoker — puts a +1/+1 counter on itself

190 other cards care about it too. These are the ones with the most connections.