While the item is held, grants a spinning top orbital that blocks enemy shots and deals contact damage (3.5 per tick, or 10.5 per second).
While the item is being used (i.e the "use item" key is held), gives Isaac +0.5 speed and improves the contact damage on Isaac's familiar, even if they do not normally deal any. Additionally, orbital familiars spin much faster and knock back both enemies and Isaac when they deal damage.
The contact damage improves to (1.5 x contact damage + 6).
If a familiar has no contact damage naturally, it still receives the +6.
The Speed given by Spin To Win can bypass the normal cap of 2.0.
Isaac can stop using Spin to Win at any time by releasing the use item button, at which point Spin to Win starts recharging.
Blue flies and blue spiders are also affected, and don't disappear while the item is in use.
Book of Virtues: Generates up to eight wisps while charging the item, which are immediately extinguished once the charge runs out. The fire rate of the wisps is based on the speed they're rotating.
The Forgotten: While as The Soul, channeling Spin to Win will cause the Forgotten's skeleton to deal contact damage.
BFFS!: The +6 contact damage bonus is not increased. Most notably, this means familiars without natural contact damage do not gain additional damage, and others gain less than expected.
Mom's Razor: Mom's Razor deals a fixed 16.5 contact damage, instead of its usual damage-scaled value, while Spin to Win is active.
Tainted Forgotten: Unlike the non-tainted counterpart, Tainted Forgotten's body gains no extra contact damage while Spin to Win is active. Additionally, Tainted Forgotten's contact damage familiars have only 80% of their usual damage.
Void: After absorbing Spin to Win, using Void spawns a temporary, passive Spin to Win familiar for the room. It cannot be activated further for the damage and speed bonuses.
The term 'spin to win' is a term that is associated with RNG based games, specifically ones that utilize a game show wheel.
The pattern on the top is reminiscent to a multicolored game show wheel, which further cements the origin of the name.
Spin to Win's item description of 'Let it Rip' is the tagline for Beyblade, which is a toy line and anime centered around battling tops.
PC PATP PBMS (Treasure Room adjacent to spawn)
PC YYD1 4T1Q (Treasure room, 2 additional orbitals obtained early on)
With Book of Virtues, leaving a room just before the item's charge runs out causes all wisps generated by Spin to Win to remain with Isaac, and will retain their very high fire rate.
The wisps will orbit at their normal speed rather than the increased speed.
Upon entering an uncompleted boss room, all wisps from this effect are extinguished immediately.